The Foundation Framework

爱被打了一巴掌 2022-08-18 03:28 144阅读 0赞

[Classes ][Classes] [Protocols ][Protocols] [Other Reference][]

The Foundation framework defines a base layer of Objective-C classes. In addition to providing a set of useful primitive object classes, it introduces several paradigms that define functionality not covered by the Objective-C language. The Foundation framework is designed with these goals in mind:

*  Provide a small set of basic utility classes.
 *  Make software development easier by introducing consistent conventions for things such as deallocation.
 *  Support Unicode strings, object persistence, and object distribution.
 *  Provide a level of OS independence, to enhance portability.

The Foundation framework includes the root object class, classes representing basic data types such as strings and byte arrays, collection classes for storing other objects, classes representing system information such as dates, and classes representing communication ports. See Cocoa Objective-C Hierarchy for Foundation for a list of those classes that make up the Foundation framework.

The Foundation framework introduces several paradigms to avoid confusion in common situations, and to introduce a level of consistency across class hierarchies. This consistency is done with some standard policies, such as that for object ownership (that is, who is responsible for disposing of objects), and with abstract classes like `NSEnumerator`. These new paradigms reduce the number of special and exceptional cases in an API and allow you to code more efficiently by reusing the same mechanisms with various kinds of objects.

### Foundation Framework Classes ###

The Foundation class hierarchy is rooted in the Foundation framework’s `NSObject` class. The remainder of the Foundation framework consists of several related groups of classes as well as a few individual classes. Many of the groups form what are called class clusters—abstract classes that work as umbrella interfaces to a versatile set of private subclasses. `NSString` and `NSMutableString`, for example, act as brokers for instances of various private subclasses optimized for different kinds of storage needs. Depending on the method you use to create a string, an instance of the appropriate optimized class will be returned to you.

Many of these classes have closely related functionality:

*  Data Storage: `NSData` provides object-oriented storage for arrays of bytes. `NSValue` and `NSNumber` provide object-oriented storage for arrays of simple C data values. `NSArray`, `NSDictionary`, and `NSSet` provide storage for Objective-C objects of any class.
    
    See [Number and Value Programming Topics][] and [Collections Programming Topics][] for more information.
 *  Text and Strings: The `NSString` and `NSMutableString` classes represent text strings and provide methods for searching, combining, and comparing strings. An `NSScanner` object is used to scan numbers and words from an `NSString` object. `NSCharacterSet` represents various groupings of characters that are used by `NSString` and `NSScanner`.
    
    See [String Programming Guide][] for more information.
 *  Dates and Times: The `NSDate`, `NSTimeZone`, and `NSCalendar` classes store times and dates and represent calendrical information. They offer methods for calculating date and time differences. Together with `NSLocale`, they provide methods for displaying dates and times in many formats, and for adjusting times and dates based on location in the world.
    
    See [Date and Time Programming Guide][] for more information.
 *  Sorting and Filtering: Collections of Objective-C objects, such as `NSArray`, `NSDictionary`, and `NSSet`, can be filtered by an `NSPredicate` object, and sorted by one or more `NSSortDescriptor` objects.
    
    See [Sort Descriptor Programming Topics][] and [Predicate Programming Guide][] for more information.
 *  Application Coordination and Timing: `NSNotification`, `NSNotificationCenter`, and `NSNotificationQueue` provide systems that an object can use to notify all interested observers of changes that occur. You can use an `NSTimer` object to send a message to another object at specific intervals.
    
    See [Notification Programming Topics][] for more information.
 *  Object Distribution and Persistence: The data that an object contains can be represented in an architecture-independent way using`NSPropertyListSerialization` and `NSJSONSerialization`. The `NSCoder` class and its subclasses take this process a step further by allowing class information to be stored along with the data. The resulting representations are used for archiving and for object distribution.
    
    See [Archives and Serializations Programming Guide][] for more information.
 *  Operating-System Services: Several classes are designed to insulate you from the idiosyncrasies of various operating systems.`NSFileManager` provides a consistent interface for file operations (creating, renaming, deleting, and so on). `NSThread` and `NSProcessInfo` let you create multithreaded applications and query the environment in which an application runs.
    
    See [File System Programming Guide][] for more information.
 *  URL Loading System: A set of classes and protocols that allow your app to access content referenced by a URL, as represented by the`NSURL` class. `NSURLRequest` and `NSURLResponse` objects represent requests and responses sent and received by an `NSURLSession` object. Additional functionality is provided by helper classes, including `NSURLProtocol` for protocol support, `NSURLAuthenticationChallenge` and `NSURLCredentialStorage`for authentication and credentials, `NSHTTPCookieStorage` for cookie storage, and `NSURLCache` for cache management.
    
    See [URL Session Programming Guide][] for more information.

### Classes ###

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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; width:246px"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:12px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSObject_Class/index.html#//apple_ref/occ/cl/NSObject" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSObject</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> NSObject is the root class of most Objective-C class hierarchies. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSArray_Class/index.html#//apple_ref/occ/cl/NSArray" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSArray</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> NSArray and its subclass NSMutableArray manage ordered collections of objects called arrays. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:42px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSMutableArray_Class/index.html#//apple_ref/occ/cl/NSMutableArray" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSMutableArray</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSMutableArray class declares the programmatic interface to objects that manage a modifiable array of objects. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSAssertionHandler_Class/index.html#//apple_ref/occ/cl/NSAssertionHandler" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSAssertionHandler</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> NSAssertionHandler objects are automatically created to handle false assertions. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSAttributedString_Class/index.html#//apple_ref/occ/cl/NSAttributedString" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSAttributedString</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> An NSAttributedString object manages character strings and associated sets of attributes (for example, font and kerning) that apply to individual characters or ranges of characters in the string. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:42px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSMutableAttributedString_Class/index.html#//apple_ref/occ/cl/NSMutableAttributedString" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSMutableAttributedString</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> NSMutableAttributedString declares the programmatic interface to objects that manage mutable attributed strings. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSAutoreleasePool_Class/index.html#//apple_ref/occ/cl/NSAutoreleasePool" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSAutoreleasePool</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSAutoreleasePool class is used to support Cocoa’s reference-counted memory management system. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSBundle_Class/index.html#//apple_ref/occ/cl/NSBundle" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSBundle</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> An NSBundle object represents a location in the file system that groups code and resources that can be used in a program. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> An NSBundleResourceRequest object manages the availability of on-demand resources. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/NSCache_Class/index.html#//apple_ref/occ/cl/NSCache" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSCache</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> An NSCache object is a collection-like container, or cache, that stores key-value pairs, similar to the NSDictionary class. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSCachedURLResponse_Class/index.html#//apple_ref/occ/cl/NSCachedURLResponse" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSCachedURLResponse</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> An NSCachedURLResponse object represents a cached response to a URL request. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSCalendar_Class/index.html#//apple_ref/occ/cl/NSCalendar" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSCalendar</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> Calendars encapsulate information about systems of reckoning time in which the beginning, length, and divisions of a year are defined. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSCharacterSet_Class/index.html#//apple_ref/occ/cl/NSCharacterSet" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSCharacterSet</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> An NSCharacterSet object represents a set of Unicode-compliant characters. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:42px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSMutableCharacterSet_Class/index.html#//apple_ref/occ/cl/NSMutableCharacterSet" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSMutableCharacterSet</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSMutableCharacterSet class declares the programmatic interface to objects that manage a modifiable set of Unicode characters. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSCoder_Class/index.html#//apple_ref/occ/cl/NSCoder" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSCoder</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSCoder abstract class declares the interface used by concrete subclasses to transfer objects and other values between memory and some other format. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:42px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSKeyedArchiver_Class/index.html#//apple_ref/occ/cl/NSKeyedArchiver" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSKeyedArchiver</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> NSKeyedArchiver, a concrete subclass of NSCoder, provides a way to encode objects (and scalar values) into an architecture-independent format that can be stored in a file. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:42px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSKeyedUnarchiver_Class/index.html#//apple_ref/occ/cl/NSKeyedUnarchiver" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSKeyedUnarchiver</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> NSKeyedUnarchiver, a concrete subclass of NSCoder, defines methods for decoding a set of named objects (and scalar values) from a keyed archive. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/NSCondition_class/index.html#//apple_ref/occ/cl/NSCondition" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSCondition</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSCondition class implements a condition variable whose semantics follow those used for POSIX-style conditions. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSConditionLock_Class/index.html#//apple_ref/occ/cl/NSConditionLock" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSConditionLock</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSConditionLock class defines objects whose locks can be associated with specific, user-defined conditions. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSData_Class/index.html#//apple_ref/occ/cl/NSData" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSData</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> NSData and its mutable subclass NSMutableData provide data objects, object-oriented wrappers for byte buffers. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:42px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSMutableData_Class/index.html#//apple_ref/occ/cl/NSMutableData" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSMutableData</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> NSMutableData (and its superclass NSData) provide data objects, object-oriented wrappers for byte buffers. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:57px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/NSPurgeableData_Class/index.html#//apple_ref/occ/cl/NSPurgeableData" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSPurgeableData</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> You should use the NSPurgeableData class when you have objects with bytes that can be discarded when no longer needed. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSDate_Class/index.html#//apple_ref/occ/cl/NSDate" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSDate</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> NSDate objects encapsulate a single point in time, independent of any particular calendrical system or time zone. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSDateComponents_Class/index.html#//apple_ref/occ/cl/NSDateComponents" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSDateComponents</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> NSDateComponents encapsulates the components of a date in an extendable, object-oriented manner. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSDecimalNumberHandler_Class/index.html#//apple_ref/occ/cl/NSDecimalNumberHandler" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSDecimalNumberHandler</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> NSDecimalNumberHandler is a class that adopts the NSDecimalNumberBehaviors protocol. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSDictionary_Class/index.html#//apple_ref/occ/cl/NSDictionary" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSDictionary</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSDictionary class declares the programmatic interface to objects that manage immutable associations of keys and values. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:42px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSMutableDictionary_Class/index.html#//apple_ref/occ/cl/NSMutableDictionary" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSMutableDictionary</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSMutableDictionary class declares the programmatic interface to objects that manage mutable associations of keys and values. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSEnumerator_Class/index.html#//apple_ref/occ/cl/NSEnumerator" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSEnumerator</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> NSEnumerator is an abstract class, instances of whose subclasses enumerate collections of other objects, such as arrays and dictionaries. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:42px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSDirectoryEnumerator_Class/index.html#//apple_ref/occ/cl/NSDirectoryEnumerator" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSDirectoryEnumerator</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> An NSDirectoryEnumerator object enumerates the contents of a directory, returning the pathnames of all files and directories contained within that directory. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSError_Class/index.html#//apple_ref/occ/cl/NSError" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSError</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> An NSError object encapsulates information about an error condition in an extendable, object-oriented manner. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSException_Class/index.html#//apple_ref/occ/cl/NSException" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSException</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> NSException is used to implement exception handling and contains information about an exception. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSExpression_Class/index.html#//apple_ref/occ/cl/NSExpression" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSExpression</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> NSExpression is used to represent expressions in a predicate. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Foundation/Reference/NSExtensionContext_Class/index.html#//apple_ref/occ/cl/NSExtensionContext" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSExtensionContext</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> An NSExtensionContext object represents the host app context from which an app extension is invoked. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Foundation/Reference/NSExtensionItem_Class/index.html#//apple_ref/occ/cl/NSExtensionItem" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSExtensionItem</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> An NSExtensionItem object is an immutable collection of values representing different aspects of an item for the extension to act upon. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Foundation/Reference/NSFileAccessIntent_Class/index.html#//apple_ref/occ/cl/NSFileAccessIntent" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSFileAccessIntent</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSFileAccessIntent class stores the details of coordinated-read and coordinated-write operations. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Foundation/Reference/NSFileCoordinator_class/index.html#//apple_ref/occ/cl/NSFileCoordinator" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSFileCoordinator</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSFileCoordinator class coordinates the reading and writing of files and directories among multiple processes and objects in the same process. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSFileHandle_Class/index.html#//apple_ref/occ/cl/NSFileHandle" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSFileHandle</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSFileHandle class is an object-oriented wrapper for a file descriptor. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSFileManager_Class/index.html#//apple_ref/occ/cl/NSFileManager" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSFileManager</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> An NSFileManager object lets you examine the contents of the file system and make changes to it. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Foundation/Reference/NSFileSecurity_class/index.html#//apple_ref/occ/cl/NSFileSecurity" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSFileSecurity</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSFileSecurity class is an Objective-C stub class that is transparently bridged to CFFileSecurity. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Foundation/Reference/NSFileVersion_Class/index.html#//apple_ref/occ/cl/NSFileVersion" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSFileVersion</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> An NSFileVersion object represents a snapshot of a file at a specific point in time. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/ApplicationKit/Classes/NSFileWrapper_Class/index.html#//apple_ref/occ/cl/NSFileWrapper" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSFileWrapper</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSFileWrapper class provides access to the attributes and contents of file-system nodes. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSFormatter_Class/index.html#//apple_ref/occ/cl/NSFormatter" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSFormatter</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> NSFormatter is an abstract class that declares an interface for objects that create, interpret, and validate the textual representation of values. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:42px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Foundation/Reference/NSByteCountFormatter_Class/index.html#//apple_ref/occ/cl/NSByteCountFormatter" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSByteCountFormatter</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSByteCountFormatter class converts a byte count value into a textual representation that is formatted with the appropriate byte modifier (KB, MB, GB and so on). </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:42px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Foundation/Reference/NSDateComponentsFormatter_class/index.html#//apple_ref/occ/cl/NSDateComponentsFormatter" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSDateComponentsFormatter</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> An NSDateComponentsFormatter object takes quantities of time and formats them as a user-readable string. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:42px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSDateFormatter_Class/index.html#//apple_ref/occ/cl/NSDateFormatter" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSDateFormatter</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> Instances of NSDateFormatter create string representations of NSDate objects, and convert textual representations of dates and times into NSDate objects. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:42px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Foundation/Reference/NSDateIntervalFormatter_class/index.html#//apple_ref/occ/cl/NSDateIntervalFormatter" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSDateIntervalFormatter</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> An NSDateIntervalFormatter object creates user-readable strings from pairs of dates. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:42px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Miscellaneous/Reference/NSEnergyFormatter_Class/index.html#//apple_ref/occ/cl/NSEnergyFormatter" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSEnergyFormatter</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSEnergyFormatter class provides properly formatted, localized descriptions of energy values. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:42px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Miscellaneous/Reference/NSLengthFormatter_Class/index.html#//apple_ref/occ/cl/NSLengthFormatter" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSLengthFormatter</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSLengthFormatter class provides properly formatted, localized descriptions of linear distances (for example, length and height measurements). </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:42px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Miscellaneous/Reference/NSMassFormatter_Class/index.html#//apple_ref/occ/cl/NSMassFormatter" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSMassFormatter</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSMassFormatter class provides properly formatted, localized descriptions of mass and weight values. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:42px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSNumberFormatter_Class/index.html#//apple_ref/occ/cl/NSNumberFormatter" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSNumberFormatter</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> Instances of NSNumberFormatter format the textual representation of cells that contain NSNumber objects and convert textual representations of numeric values into NSNumber objects. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:42px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Miscellaneous/Reference/NSPersonNameComponentsFormatter_Class/index.html#//apple_ref/occ/cl/NSPersonNameComponentsFormatter" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSPersonNameComponentsFormatter</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSPersonNameComponentsFormatter class provides properly formatted, localized representations of the components of a person’s name. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSHTTPCookie_Class/index.html#//apple_ref/occ/cl/NSHTTPCookie" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSHTTPCookie</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> An NSHTTPCookie object represents an HTTP cookie. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSHTTPCookieStorage_Class/index.html#//apple_ref/occ/cl/NSHTTPCookieStorage" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSHTTPCookieStorage</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> NSHTTPCookieStorage implements a singleton object (shared instance) that manages storage of cookies. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/NSHashTable_class/index.html#//apple_ref/occ/cl/NSHashTable" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSHashTable</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> NSHashTable is modeled after NSSet but provides different options, in particular to support weak relationships. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSIndexPath_Class/index.html#//apple_ref/occ/cl/NSIndexPath" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSIndexPath</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSIndexPath class represents the path to a specific node in a tree of nested array collections. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSIndexSet_Class/index.html#//apple_ref/occ/cl/NSIndexSet" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSIndexSet</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSIndexSet class represents an immutable collection of unique unsigned integers, known as indexes because of the way they are used. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:42px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSMutableIndexSet_Class/index.html#//apple_ref/occ/cl/NSMutableIndexSet" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSMutableIndexSet</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSMutableIndexSet class represents a mutable collection of unique unsigned integers, known as indexes because of the way they are used. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSInvocation_Class/index.html#//apple_ref/occ/cl/NSInvocation" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSInvocation</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> An NSInvocation is an Objective-C message rendered static, that is, it is an action turned into an object. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Foundation/Reference/NSItemProvider_Class/index.html#//apple_ref/occ/cl/NSItemProvider" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSItemProvider</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> An NSItemProvider object provides a lazy and secure way to convey data between a host app and extension. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Foundation/Reference/NSJSONSerialization_Class/index.html#//apple_ref/occ/cl/NSJSONSerialization" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSJSONSerialization</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> You use the NSJSONSerialization class to convert JSON to Foundation objects and convert Foundation objects to JSON. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/NSLinguisticTagger_Class/index.html#//apple_ref/occ/cl/NSLinguisticTagger" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSLinguisticTagger</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSLinguisticTagger class is used to automatically segment natural-language text and tag it with information, such as parts of speech. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSLocale_Class/index.html#//apple_ref/occ/cl/NSLocale" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSLocale</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> Locales encapsulate information about linguistic, cultural, and technological conventions and standards. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSLock_Class/index.html#//apple_ref/occ/cl/NSLock" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSLock</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> An NSLock object is used to coordinate the operation of multiple threads of execution within the same application. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/NSMapTable_class/index.html#//apple_ref/occ/cl/NSMapTable" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSMapTable</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> NSMapTable is a mutable collection modeled after NSDictionary but provides different options. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSMetadataItem_Class/index.html#//apple_ref/occ/cl/NSMetadataItem" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSMetadataItem</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSMetadataItem class represents the metadata associated with a file, providing a simple interface to retrieve the available attribute names and values. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSMetadataQuery_Class/index.html#//apple_ref/occ/cl/NSMetadataQuery" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSMetadataQuery</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSMetadataQuery class encapsulates the functionality provided by the MDQuery opaque type for querying the Spotlight metadata. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSMetadataQueryAttributeValueTuple_Class/index.html#//apple_ref/occ/cl/NSMetadataQueryAttributeValueTuple" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSMetadataQueryAttributeValueTuple</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSMetadataQueryAttributeValueTuple class represents attribute-value tuples, which are objects that contain the attribute name and value of a metadata attribute. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSMetadataQueryResultGroup_Class/index.html#//apple_ref/occ/cl/NSMetadataQueryResultGroup" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSMetadataQueryResultGroup</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSMetadataQueryResultGroup class represents a collection of grouped attribute results returned by an NSMetadataQuery object. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSMethodSignature_Class/index.html#//apple_ref/occ/cl/NSMethodSignature" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSMethodSignature</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> An NSMethodSignature object records type information for the arguments and return value of a method. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSNetService_Class/index.html#//apple_ref/occ/cl/NSNetService" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSNetService</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSNetService class represents a network service, either one your application publishes or is a client of. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSNetServiceBrowser_Class/index.html#//apple_ref/occ/cl/NSNetServiceBrowser" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSNetServiceBrowser</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSNetServiceBrowser class defines an interface for finding published services on a network using multicast DNS. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSNotification_Class/index.html#//apple_ref/occ/cl/NSNotification" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSNotification</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> NSNotification objects encapsulate information so that it can be broadcast to other objects by an NSNotificationCenter object. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSNotificationCenter_Class/index.html#//apple_ref/occ/cl/NSNotificationCenter" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSNotificationCenter</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> An NSNotificationCenter object (or simply, notification center) provides a mechanism for broadcasting information within a program. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSNotificationQueue_Class/index.html#//apple_ref/occ/cl/NSNotificationQueue" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSNotificationQueue</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> NSNotificationQueue objects (or simply notification queues) act as buffers for notification centers (instances of NSNotificationCenter). </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSNull_Class/index.html#//apple_ref/occ/cl/NSNull" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSNull</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSNull class defines a singleton object used to represent null values in collection objects (which don’t allow nil values). </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/NSOperation_class/index.html#//apple_ref/occ/cl/NSOperation" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSOperation</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSOperation class is an abstract class you use to encapsulate the code and data associated with a single task. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:42px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/NSBlockOperation_class/index.html#//apple_ref/occ/cl/NSBlockOperation" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSBlockOperation</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSBlockOperation class is a concrete subclass of NSOperation that manages the concurrent execution of one or more blocks. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:42px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/NSInvocationOperation_Class/index.html#//apple_ref/occ/cl/NSInvocationOperation" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSInvocationOperation</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSInvocationOperation class is a concrete subclass of NSOperation that manages the execution of a single encapsulated task specified as an invocation. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/NSOperationQueue_class/index.html#//apple_ref/occ/cl/NSOperationQueue" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSOperationQueue</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSOperationQueue class regulates the execution of a set of NSOperation objects. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Foundation/Reference/NSOrderedSet_Class/index.html#//apple_ref/occ/cl/NSOrderedSet" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSOrderedSet</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> NSOrderedSet and its subclass, NSMutableOrderedSet, declare the programmatic interfaces to an ordered collection of objects. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:42px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Foundation/Reference/NSMutableOrderedSet_Class/index.html#//apple_ref/occ/cl/NSMutableOrderedSet" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSMutableOrderedSet</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> NSMutableOrderedSet class declares the programmatic interface to a mutable, ordered collection of distinct objects. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/NSOrthography_Class/index.html#//apple_ref/occ/cl/NSOrthography" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSOrthography</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSOrthography class describes the linguistic content of a piece of text, typically used for the purposes of spelling and grammar checking. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Miscellaneous/Reference/NSPersonNameComponents_Class/index.html#//apple_ref/occ/cl/NSPersonNameComponents" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSPersonNameComponents</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> An NSPersonNameComponents object encapsulates the components of a person's name in an extendable, object-oriented manner. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSPipe_Class/index.html#//apple_ref/occ/cl/NSPipe" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSPipe</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> NSPipe objects provide an object-oriented interface for accessing pipes. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSPointerArray_Class/index.html#//apple_ref/occ/cl/NSPointerArray" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSPointerArray</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> NSPointerArray is a mutable collection modeled after NSArray but it can also hold NULL values, which can be inserted or extracted (and which contribute to the object’s count). </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSPointerFunctions_Class/index.html#//apple_ref/occ/cl/NSPointerFunctions" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSPointerFunctions</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> An instance of NSPointerFunctions defines callout functions appropriate for managing a pointer reference held somewhere else. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSPort_Class/index.html#//apple_ref/occ/cl/NSPort" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSPort</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> NSPort is an abstract class that represents a communication channel. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:42px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSMachPort_Class/index.html#//apple_ref/occ/cl/NSMachPort" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSMachPort</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> NSMachPort is a subclass of NSPort that can be used as an endpoint for distributed object connections (or raw messaging). </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:42px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSMessagePort_Class/index.html#//apple_ref/occ/cl/NSMessagePort" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSMessagePort</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> NSMessagePort is a subclass of NSPort that can be used as an endpoint for distributed object connections (or raw messaging). </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSPredicate_Class/index.html#//apple_ref/occ/cl/NSPredicate" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSPredicate</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSPredicate class is used to define logical conditions used to constrain a search either for a fetch or for in-memory filtering. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:42px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSComparisonPredicate_Class/index.html#//apple_ref/occ/cl/NSComparisonPredicate" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSComparisonPredicate</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> NSComparisonPredicate is a subclass of NSPredicate that you use to compare expressions. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:42px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSCompoundPredicate_Class/index.html#//apple_ref/occ/cl/NSCompoundPredicate" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSCompoundPredicate</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> NSCompoundPredicate is a subclass of NSPredicate used to represent logical “gate” operations (AND/OR/NOT) and comparison operations. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSProcessInfo_Class/index.html#//apple_ref/occ/cl/NSProcessInfo" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSProcessInfo</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSProcessInfo class provides methods to access information about the current process. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Foundation/Reference/NSProgress_Class/index.html#//apple_ref/occ/cl/NSProgress" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSProgress</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSProgress class provides a self-contained mechanism for progress reporting. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSPropertyListSerialization_Class/index.html#//apple_ref/occ/cl/NSPropertyListSerialization" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSPropertyListSerialization</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSPropertyListSerialization class provides methods that convert property list objects to and from several serialized formats. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSRecursiveLock_Class/index.html#//apple_ref/occ/cl/NSRecursiveLock" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSRecursiveLock</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> NSRecursiveLock defines a lock that may be acquired multiple times by the same thread without causing a deadlock, a situation where a thread is permanently blocked waiting for itself to relinquish a lock. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Foundation/Reference/NSRegularExpression_Class/index.html#//apple_ref/occ/cl/NSRegularExpression" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSRegularExpression</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSRegularExpression class is used to represent and apply regular expressions to Unicode strings. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:42px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Foundation/Reference/NSDataDetector_Class/index.html#//apple_ref/occ/cl/NSDataDetector" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSDataDetector</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSDataDetector class is a specialized subclass of the NSRegularExpression class designed to match data detectors. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSRunLoop_Class/index.html#//apple_ref/occ/cl/NSRunLoop" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSRunLoop</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSRunLoop class declares the programmatic interface to objects that manage input sources. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSScanner_Class/index.html#//apple_ref/occ/cl/NSScanner" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSScanner</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSScanner class is an abstract superclass of a class cluster that declares the programmatic interface for an object that scans values from an NSString object. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSSet_Class/index.html#//apple_ref/occ/cl/NSSet" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSSet</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSSet, NSMutableSet, and NSCountedSet classes declare the programmatic interface to an unordered collection of objects. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:42px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSMutableSet_Class/index.html#//apple_ref/occ/cl/NSMutableSet" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSMutableSet</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSMutableSet class declares the programmatic interface to a mutable, unordered collection of distinct objects. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:57px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSCountedSet_Class/index.html#//apple_ref/occ/cl/NSCountedSet" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSCountedSet</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSCountedSet class declares the programmatic interface to a mutable, unordered collection of indistinct objects. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSSortDescriptor_Class/index.html#//apple_ref/occ/cl/NSSortDescriptor" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSSortDescriptor</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> An instance of NSSortDescriptor describes a basis for ordering objects by specifying the property to use to compare the objects, the method to use to compare the properties, and whether the comparison should be ascending or descending. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSStream_Class/index.html#//apple_ref/occ/cl/NSStream" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSStream</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> NSStream is an abstract class for objects representing streams. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:42px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSInputStream_Class/index.html#//apple_ref/occ/cl/NSInputStream" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSInputStream</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> NSInputStream is a subclass of NSStream that provides read-only stream functionality. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:42px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSOutputStream_Class/index.html#//apple_ref/occ/cl/NSOutputStream" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSOutputStream</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSOutputStream class is a subclass of NSStream that provides write-only stream functionality. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSString_Class/index.html#//apple_ref/occ/cl/NSString" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSString</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSString class declares the programmatic interface for an object that manages immutable strings. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:42px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSMutableString_Class/index.html#//apple_ref/occ/cl/NSMutableString" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSMutableString</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSMutableString class declares the programmatic interface to an object that manages a mutable string—that is, a string whose contents can be edited—that conceptually represents an array of Unicode characters. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/AppKit/Reference/NSTextCheckingResult_Class/index.html#//apple_ref/occ/cl/NSTextCheckingResult" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSTextCheckingResult</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> NSTextCheckingResult is a class used to describe items located by text checking. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSThread_Class/index.html#//apple_ref/occ/cl/NSThread" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSThread</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> An NSThread object controls a thread of execution. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSTimeZone_Class/index.html#//apple_ref/occ/cl/NSTimeZone" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSTimeZone</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> NSTimeZone is an abstract class that defines the behavior of time zone objects. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSTimer_Class/index.html#//apple_ref/occ/cl/NSTimer" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSTimer</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> You use the NSTimer class to create timer objects or, more simply, timers. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSURL_Class/index.html#//apple_ref/occ/cl/NSURL" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSURL</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> An NSURL object represents a URL that can potentially contain the location of a resource on a remote server, the path of a local file on disk, or even an arbitrary piece of encoded data. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSURLAuthenticationChallenge_Class/index.html#//apple_ref/occ/cl/NSURLAuthenticationChallenge" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSURLAuthenticationChallenge</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> NSURLAuthenticationChallenge encapsulates a challenge from a server requiring authentication from the client. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSURLCache_Class/index.html#//apple_ref/occ/cl/NSURLCache" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSURLCache</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSURLCache class implements the caching of responses to URL load requests by mapping NSURLRequest objects to NSCachedURLResponse objects. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Foundation/Reference/NSURLComponents_class/index.html#//apple_ref/occ/cl/NSURLComponents" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSURLComponents</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSURLComponents class is a class that is designed to parse URLs based on RFC 3986 and to construct URLs from their constituent parts. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSURLConnection_Class/index.html#//apple_ref/occ/cl/NSURLConnection" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSURLConnection</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> An NSURLConnection object lets you load the contents of a URL by providing a URL request object. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSURLCredential_Class/index.html#//apple_ref/occ/cl/NSURLCredential" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSURLCredential</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> NSURLCredential is an immutable object representing an authentication credential consisting of authentication information specific to the type of credential and the type of persistent storage to use, if any. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSURLCredentialStorage_Class/index.html#//apple_ref/occ/cl/NSURLCredentialStorage" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSURLCredentialStorage</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> NSURLCredentialStorage implements a singleton (shared object) that manages the credential storage. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSURLProtectionSpace_Class/index.html#//apple_ref/occ/cl/NSURLProtectionSpace" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSURLProtectionSpace</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> An NSURLProtectionSpace object represents a server or an area on a server, commonly referred to as a realm, that requires authentication. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSURLProtocol_Class/index.html#//apple_ref/occ/cl/NSURLProtocol" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSURLProtocol</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> An NSURLProtocol object handles the loading of protocol-specific URL data. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Foundation/Reference/NSURLQueryItem_Class/index.html#//apple_ref/occ/cl/NSURLQueryItem" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSURLQueryItem</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> An NSURLQueryItem object represents a single name/value pair for an item in the query portion of a URL. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSURLRequest_Class/index.html#//apple_ref/occ/cl/NSURLRequest" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSURLRequest</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> NSURLRequest objects represent a URL load request in a manner independent of protocol and URL scheme. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:42px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSMutableURLRequest_Class/index.html#//apple_ref/occ/cl/NSMutableURLRequest" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSMutableURLRequest</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> NSMutableURLRequest is a subclass of NSURLRequest provided to aid developers who may find it more convenient to mutate a single request object for a series of URL load requests instead of creating an immutable NSURLRequest object for each load. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSURLResponse_Class/index.html#//apple_ref/occ/cl/NSURLResponse" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSURLResponse</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSURLResponse class encapsulates the metadata associated with the response to a a URL load request in a manner independent of protocol and URL scheme. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:42px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSHTTPURLResponse_Class/index.html#//apple_ref/occ/cl/NSHTTPURLResponse" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSHTTPURLResponse</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSHTTPURLResponse class is a subclass of NSURLResponse that provides methods for accessing information specific to HTTP protocol responses. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Foundation/Reference/NSURLSession_class/index.html#//apple_ref/occ/cl/NSURLSession" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSURLSession</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSURLSession class and related classes provide an API for downloading content. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Foundation/Reference/NSURLSessionConfiguration_class/index.html#//apple_ref/occ/cl/NSURLSessionConfiguration" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSURLSessionConfiguration</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> An NSURLSessionConfiguration object defines the behavior and policies to use when uploading and downloading data using an NSURLSession object. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Foundation/Reference/NSURLSessionTask_class/index.html#//apple_ref/occ/cl/NSURLSessionTask" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSURLSessionTask</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSURLSessionTask class is the base class for tasks in a URL session. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:42px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Foundation/Reference/NSURLSessionDataTask_class/index.html#//apple_ref/occ/cl/NSURLSessionDataTask" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSURLSessionDataTask</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> An NSURLSessionDataTask is a concrete subclass of NSURLSessionTask. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:57px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Foundation/Reference/NSURLSessionUploadTask_class/index.html#//apple_ref/occ/cl/NSURLSessionUploadTask" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSURLSessionUploadTask</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSURLSessionUploadTask class is a subclass of NSURLSessionDataTask, which in turn is a concrete subclass of NSURLSessionTask. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:42px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Foundation/Reference/NSURLSessionDownloadTask_class/index.html#//apple_ref/occ/cl/NSURLSessionDownloadTask" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSURLSessionDownloadTask</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> An NSURLSessionDownloadTask is a concrete subclass of NSURLSessionTask. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:42px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent">NSURLSessionStreamTask</code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Foundation/Reference/NSUUID_Class/index.html#//apple_ref/occ/cl/NSUUID" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSUUID</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSUUID class creates UUID strings that are to uniquely identify types, interfaces, and other items. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Foundation/Reference/NSUbiquitousKeyValueStore_class/index.html#//apple_ref/occ/cl/NSUbiquitousKeyValueStore" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSUbiquitousKeyValueStore</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> Use the iCloud key-value store to make preference, configuration, and app-state data available to every instance of your app on every device connected to a user’s iCloud account. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSUndoManager_Class/index.html#//apple_ref/occ/cl/NSUndoManager" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSUndoManager</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> NSUndoManager is a general-purpose recorder of operations for undo and redo. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Foundation/Reference/NSUserActivity_Class/index.html#//apple_ref/occ/cl/NSUserActivity" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSUserActivity</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> An NSUserActivity object provides a lightweight way to capture app state so that it can be restored later. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSUserDefaults_Class/index.html#//apple_ref/occ/cl/NSUserDefaults" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSUserDefaults</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> The NSUserDefaults class provides a programmatic interface for interacting with the defaults system. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSValue_Class/index.html#//apple_ref/occ/cl/NSValue" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSValue</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> An NSValue object is a simple container for a single C or Objective-C data item. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:42px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSNumber_Class/index.html#//apple_ref/occ/cl/NSNumber" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSNumber</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> NSNumber is a subclass of NSValue that offers a value as any C scalar (numeric) type. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:57px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSDecimalNumber_Class/index.html#//apple_ref/occ/cl/NSDecimalNumber" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSDecimalNumber</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> NSDecimalNumber, an immutable subclass of NSNumber, provides an object-oriented wrapper for doing base-10 arithmetic. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSValueTransformer_Class/index.html#//apple_ref/occ/cl/NSValueTransformer" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSValueTransformer</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> NSValueTransformer is an abstract class that is used by the Cocoa Bindings technology to transform values from one representation to another. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:27px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSXMLParser_Class/index.html#//apple_ref/occ/cl/NSXMLParser" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSXMLParser</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> Instances of this class parse XML documents (including DTD declarations) in an event-driven manner. </td> 
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 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; padding-left:12px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> <code style="border:0px; font-size:0.85em; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(128,128,128); font-family:Menlo,monospace; word-wrap:break-word; background:transparent"><a href="https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSProxy_Class/index.html#//apple_ref/occ/cl/NSProxy" style="border:0px; font-size:12px; margin:0px; outline:0px; padding:0px; vertical-align:baseline; color:rgb(0,136,204); text-decoration:none; background:transparent" rel="nofollow">NSProxy</a></code> </td> 
 <td style="border:0px; margin:0px; outline:0px; padding:5px 15px 5px 0px; vertical-align:top; max-width:inherit; background:transparent"> <p style="border:0px; font-size:1.4em; margin-top:0px; margin-bottom:0px; outline:0px; padding-top:0px; padding-bottom:0px; vertical-align:baseline; color:rgb(65,65,65); line-height:20.2999992370605px; background:transparent"> NSProxy is an abstract superclass defining an API for objects that act as stand-ins for other objects or for objects that don’t exist yet. </td> 
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 </tbody> 
</table>

### Protocols ###

### Other Reference ###

[Classes ][Classes] [Protocols ][Protocols] [Other Reference][]

### Foundation Framework Classes ###

Many of these classes have closely related functionality:

*  **Data Storage**: `NSData` provides object-oriented storage for arrays of bytes. `NSValue` and `NSNumber` provide object-oriented storage for arrays of simple C data values. `NSArray`, `NSDictionary`, and `NSSet` provide storage for Objective-C objects of any class.
    
    See *[Number and Value Programming Topics][]* and *[Collections Programming Topics][]* for more information.
 *  **Text and Strings**: The `NSString` and `NSMutableString` classes represent text strings and provide methods for searching, combining, and comparing strings. An `NSScanner` object is used to scan numbers and words from an `NSString` object. `NSCharacterSet` represents various groupings of characters that are used by `NSString` and `NSScanner`.
    
    See *[String Programming Guide][]* for more information.
 *  **Dates and Times**: The `NSDate`, `NSTimeZone`, and `NSCalendar` classes store times and dates and represent calendrical information. They offer methods for calculating date and time differences. Together with `NSLocale`, they provide methods for displaying dates and times in many formats, and for adjusting times and dates based on location in the world.
    
    See *[Date and Time Programming Guide][]* for more information.
 *  **Sorting and Filtering**: Collections of Objective-C objects, such as `NSArray`, `NSDictionary`, and `NSSet`, can be filtered by an `NSPredicate` object, and sorted by one or more `NSSortDescriptor` objects.
    
    See *[Sort Descriptor Programming Topics][]* and *[Predicate Programming Guide][]* for more information.
 *  **Application Coordination and Timing**: `NSNotification`, `NSNotificationCenter`, and `NSNotificationQueue` provide systems that an object can use to notify all interested observers of changes that occur. You can use an `NSTimer` object to send a message to another object at specific intervals.
    
    See *[Notification Programming Topics][]* for more information.
 *  **Object Distribution and Persistence**: The data that an object contains can be represented in an architecture-independent way using`NSPropertyListSerialization` and `NSJSONSerialization`. The `NSCoder` class and its subclasses take this process a step further by allowing class information to be stored along with the data. The resulting representations are used for archiving and for object distribution.
    
    See *[Archives and Serializations Programming Guide][]* for more information.
 *  **Operating-System Services**: Several classes are designed to insulate you from the idiosyncrasies of various operating systems.`NSFileManager` provides a consistent interface for file operations (creating, renaming, deleting, and so on). `NSThread` and `NSProcessInfo` let you create multithreaded applications and query the environment in which an application runs.
    
    See *[File System Programming Guide][]* for more information.
 *  **URL Loading System**: A set of classes and protocols that allow your app to access content referenced by a URL, as represented by the`NSURL` class. `NSURLRequest` and `NSURLResponse` objects represent requests and responses sent and received by an `NSURLSession` object. Additional functionality is provided by helper classes, including `NSURLProtocol` for protocol support, `NSURLAuthenticationChallenge` and `NSURLCredentialStorage`for authentication and credentials, `NSHTTPCookieStorage` for cookie storage, and `NSURLCache` for cache management.
    
    See *[URL Session Programming Guide][]* for more information.

### Classes ###

### Protocols ###

### Other Reference ###

[Classes]: https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/ObjC_classic/index.html#classes
[Protocols]: https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/ObjC_classic/index.html#protocols
[Other Reference]: https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/ObjC_classic/index.html#other
[Number and Value Programming Topics]: https://developer.apple.com/library/ios/documentation/Cocoa/Conceptual/NumbersandValues/NumbersandValues.html#//apple_ref/doc/uid/10000038i
[Collections Programming Topics]: https://developer.apple.com/library/ios/documentation/Cocoa/Conceptual/Collections/Collections.html#//apple_ref/doc/uid/10000034i
[String Programming Guide]: https://developer.apple.com/library/ios/documentation/Cocoa/Conceptual/Strings/introStrings.html#//apple_ref/doc/uid/10000035i
[Date and Time Programming Guide]: https://developer.apple.com/library/ios/documentation/Cocoa/Conceptual/DatesAndTimes/DatesAndTimes.html#//apple_ref/doc/uid/10000039i
[Sort Descriptor Programming Topics]: https://developer.apple.com/library/ios/documentation/Cocoa/Conceptual/SortDescriptors/SortDescriptors.html#//apple_ref/doc/uid/10000174i
[Predicate Programming Guide]: https://developer.apple.com/library/ios/documentation/Cocoa/Conceptual/Predicates/AdditionalChapters/Introduction.html#//apple_ref/doc/uid/TP40001789
[Notification Programming Topics]: https://developer.apple.com/library/ios/documentation/Cocoa/Conceptual/Notifications/Introduction/introNotifications.html#//apple_ref/doc/uid/10000043i
[Archives and Serializations Programming Guide]: https://developer.apple.com/library/ios/documentation/Cocoa/Conceptual/Archiving/Archiving.html#//apple_ref/doc/uid/10000047i
[File System Programming Guide]: https://developer.apple.com/library/ios/documentation/FileManagement/Conceptual/FileSystemProgrammingGuide/Introduction/Introduction.html#//apple_ref/doc/uid/TP40010672
[URL Session Programming Guide]: https://developer.apple.com/library/ios/documentation/Cocoa/Conceptual/URLLoadingSystem/URLLoadingSystem.html#//apple_ref/doc/uid/10000165i