Task Scheduler

冷不防 2022-08-07 16:00 217阅读 0赞

原文：[http://www.codeproject.com/Articles/38553/Task-Scheduler][http_www.codeproject.com_Articles_38553_Task-Scheduler]

A simple structured native task scheduler

*  [Download demo project - 12.46 KB][Download demo project_- 12.46 KB]
 *  [Download source - 49.97 KB][]

![Image 1][]

## Introduction ##

Task Scheduler is a class that schedules and automatically fires events at a time you specify. All important triggers are available: `OnlyOneTime`, `Daily`, `Weekly` and `Monthly`.

### So why another Task Scheduler? ###

We need for one of our projects a scheduler that

1.  Can check a date or show all dates on which a trigger will fire.  (See the demo - button "Show List")
2.  We need to schedule tasks not only daily, weekly,... we need a combination of them. e.g. every Wednesday (weekly trigger) plus every last day in a month (monthly trigger)

Update 1: Version 1.1

*  Added date formatting during serialization/deserialization
 *  Fixed issue in TriggerItem.FromXML()

Update 2: Version 1.2

*  Now using System.Timers.Timer instead of System.Windows.Forms.Timer
 *  Minor changes in XML serialization
 *  Demo now includes a Windows-Service with full service control (start/stop/install/uninstall)
 *  TriggerItemCollection support now serialization / deserialization
 *  Bug fixes

## Features ##

*  Simple structure and easy to use
 *  Possible triggers: `OneTimeOnly`, `Daily`, `Weekly` and `Monthly`
 *  Monthly trigger: `DayOfMonth` and `Weekday`
 *  Collection of TriggerItems
 *  Next Trigger-Date/Time information
 *  Check if a TriggerItem will fire on a certain date `CheckDate(DateTime date)`
 *  Combine different triggers in one item. (e.g. every Friday plus every last day in a month)  
    If there is an overlap the Trigger will fire only one time
 *  Save and restore `TriggerItems` to and from XML

## Settings ##

<table style="margin:0px; padding:0px; border-width:1px 0px 0px 1px; border-top-style:solid; border-left-style:solid; border-top-color:rgb(204,204,204); border-left-color:rgb(204,204,204); border-collapse:collapse; color:rgb(17,17,17); font-family:'Segoe UI',Arial,sans-serif; font-size:14px"> 
 <thead style="margin:0px; padding:0px; border:0px; font-weight:bold; background-color:rgb(235,246,255)"> 
  <tr style="margin:0px; padding:0px; border:0px"> 
   <td style="margin:0px; padding:5px; border-width:0px 1px 1px 0px; border-right-style:solid; border-bottom-style:solid; border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); font-family:'Segoe UI',Arial,sans-serif; font-size:14px"> Field</td> 
   <td style="margin:0px; padding:5px; border-width:0px 1px 1px 0px; border-right-style:solid; border-bottom-style:solid; border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); font-family:'Segoe UI',Arial,sans-serif; font-size:14px"> Description</td> 
  </tr> 
 </thead> 
 <tbody style="margin:0px; padding:0px; border:0px"> 
  <tr style="margin:0px; padding:0px; border:0px"> 
   <td style="margin:0px; padding:5px; border-width:0px 1px 1px 0px; border-right-style:solid; border-bottom-style:solid; border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); font-family:'Segoe UI',Arial,sans-serif; font-size:14px"> <code style="margin:0px; padding:0px; border:0px; color:rgb(153,0,0); font-size:11pt; font-family:Consolas,'Courier New',Courier,mono">StartDate</code></td> 
   <td style="margin:0px; padding:5px; border-width:0px 1px 1px 0px; border-right-style:solid; border-bottom-style:solid; border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); font-family:'Segoe UI',Arial,sans-serif; font-size:14px"> Specifies the first date on which the trigger will fire</td> 
  </tr> 
  <tr style="margin:0px; padding:0px; border:0px"> 
   <td style="margin:0px; padding:5px; border-width:0px 1px 1px 0px; border-right-style:solid; border-bottom-style:solid; border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); font-family:'Segoe UI',Arial,sans-serif; font-size:14px"> <code style="margin:0px; padding:0px; border:0px; color:rgb(153,0,0); font-size:11pt; font-family:Consolas,'Courier New',Courier,mono">EndDate</code></td> 
   <td style="margin:0px; padding:5px; border-width:0px 1px 1px 0px; border-right-style:solid; border-bottom-style:solid; border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); font-family:'Segoe UI',Arial,sans-serif; font-size:14px"> Specifies the last date on which the trigger will fire</td> 
  </tr> 
  <tr style="margin:0px; padding:0px; border:0px"> 
   <td style="margin:0px; padding:5px; border-width:0px 1px 1px 0px; border-right-style:solid; border-bottom-style:solid; border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); font-family:'Segoe UI',Arial,sans-serif; font-size:14px"> <code style="margin:0px; padding:0px; border:0px; color:rgb(153,0,0); font-size:11pt; font-family:Consolas,'Courier New',Courier,mono">TriggerTime</code></td> 
   <td style="margin:0px; padding:5px; border-width:0px 1px 1px 0px; border-right-style:solid; border-bottom-style:solid; border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); font-family:'Segoe UI',Arial,sans-serif; font-size:14px"> Specifies the time on which the trigger will fire</td> 
  </tr> 
  <tr style="margin:0px; padding:0px; border:0px"> 
   <td style="margin:0px; padding:5px; border-width:0px 1px 1px 0px; border-right-style:solid; border-bottom-style:solid; border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); font-family:'Segoe UI',Arial,sans-serif; font-size:14px"> <code style="margin:0px; padding:0px; border:0px; color:rgb(153,0,0); font-size:11pt; font-family:Consolas,'Courier New',Courier,mono">Enabled</code></td> 
   <td style="margin:0px; padding:5px; border-width:0px 1px 1px 0px; border-right-style:solid; border-bottom-style:solid; border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); font-family:'Segoe UI',Arial,sans-serif; font-size:14px"> Enable / disable the trigger</td> 
  </tr> 
  <tr style="margin:0px; padding:0px; border:0px"> 
   <td style="margin:0px; padding:5px; border-width:0px 1px 1px 0px; border-right-style:solid; border-bottom-style:solid; border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); font-family:'Segoe UI',Arial,sans-serif; font-size:14px"> <code style="margin:0px; padding:0px; border:0px; color:rgb(153,0,0); font-size:11pt; font-family:Consolas,'Courier New',Courier,mono">TriggerSettings</code></td> 
   <td style="margin:0px; padding:5px; border-width:0px 1px 1px 0px; border-right-style:solid; border-bottom-style:solid; border-right-color:rgb(204,204,204); border-bottom-color:rgb(204,204,204); font-family:'Segoe UI',Arial,sans-serif; font-size:14px"> Set the appropriate trigger-dates as described below</td> 
  </tr> 
 </tbody> 
</table>

`TriggerItem.TriggerSettings` Overview:  
![Another\_TaskScheduler/TriggerSettings.jpg][Another_TaskScheduler_TriggerSettings.jpg]

To activate a specific date just set the appropriate flag(s):

Hide    Copy Code

// Activate Sunday on weekly trigger.
    triggerItem.TriggerSettings.Weekly.DaysOfWeek[(int)DayOfWeek.Sunday] = true;
    
    // Activate last Friday in January and February
    triggerItem.TriggerSettings.Monthly.Month[(int)TaskScheduler.MonthOfTheYeay.January] = 
        true; 
    triggerItem.TriggerSettings.Monthly.Month[(int)TaskScheduler.MonthOfTheYeay.February] = 
        true; 
    triggerItem.TriggerSettings.Monthly.DaysOfMonth[(int)TaskScheduler.DayOccurrence.Last] =
        true; 
    triggerItem.TriggerSettings.Monthly.WeekDay[(int)DayOfWeek.Sunday] = true;

## Using TaskScheduler and TriggerItems ##

1.  Create a new instance of `TaskScheduler`.
    
    Hide    Copy Code
    
        // Create the TaskScheduler
        TaskScheduler _taskScheduler = new TaskScheduler();
        
        // Set the synchronizing object to get trigger events within the main thread.
        // Important if you're using Windows Forms
        _taskScheduler.SynchronizingObject = this;
2.  Create a new Trigger-Item. Set start and end date + trigger time and if you like a tag.
    
    Hide    Copy Code
    
        TaskScheduler.TriggerItem triggerItem = new TaskScheduler.TriggerItem();
        triggerItem.Tag = textBoxlabelOneTimeOnlyTag.Text;
        triggerItem.StartDate = dateTimePickerStartDate.Value;
        triggerItem.EndDate = dateTimePickerEndDate.Value;
        triggerItem.TriggerTime = dateTimePickerTriggerTime.Value;
        // And the trigger-Event :)
        triggerItem.OnTrigger += new TaskScheduler.TriggerItem.OnTriggerEventHandler(
            triggerItem_OnTrigger);
    
    Settings for "`OneTimeOnly`"
    
    Hide    Copy Code
    
        TriggerItem.TriggerSettings.OneTimeOnly.Active = checkBoxOneTimeOnlyActive.Checked;
        triggerItem.TriggerSettings.OneTimeOnly.Date = 
            dateTimePickerOneTimeOnlyDay.Value.Date;
    
    Settings for "`Daily`"
    
    Hide    Copy Code
    
        triggerItem.TriggerSettings.Daily.Interval = (ushort)numericUpDownDaily.Value;
    
    Settings for "`Weekly`"
    
    Hide    Copy Code
    
        for (byte day = 0; day < 7; day++) // Set the active Days
        triggerItem.TriggerSettings.Weekly.DaysOfWeek[day] = 
            checkedListBoxWeeklyDays.GetItemChecked(day);
    
    Settings for "`Monthly`"
    
    Hide    Copy Code
    
        for (byte month = 0; month < 12; month++) // Set the active Months
            triggerItem.TriggerSettings.Monthly.Month[month] = 
            checkedListBoxMonthlyMonths.GetItemChecked(month);
        
        // Set the active Days (0..30 = Days, 31=last Day) for monthly trigger
        for (byte day = 0; day < 32; day++)
            triggerItem.TriggerSettings.Monthly.DaysOfMonth[day] = 
            checkedListBoxMonthlyDays.GetItemChecked(day);
        
        // Set the active weekNumber and DayOfWeek
        // e.g the first monday, or the last friday...
        // 0..4: first, second, third, fourth or last week
        
        for (byte weekNumber = 0; weekNumber < 5; weekNumber++)     
            triggerItem.TriggerSettings.Monthly.WeekDay.WeekNumber[weekNumber] = 
            checkedListBoxMonthlyWeekNumber.GetItemChecked(weekNumber);
        for (byte day = 0; day < 7; day++)
            triggerItem.TriggerSettings.Monthly.WeekDay.DayOfWeek[day] = 
            checkedListBoxMonthlyWeekDay.GetItemChecked(day);
3.  Add the trigger to the Collection and enable the Scheduler
    
    Hide    Copy Code
    
        triggerItem.Enabled = true; // Set the Item-Active - State
        _taskScheduler.AddTrigger(item); // Add the trigger to List
        _taskScheduler.Enabled = true; // Start the Scheduler

## Disclaimer ##

THE SOFTWARE AND THE ACCOMPANYING FILES ARE DISTRIBUTED "AS IS" AND WITHOUT ANY WARRANTIES WHETHER EXPRESSED OR IMPLIED. NO REPONSIBILITIES FOR POSSIBLE DAMAGES OR EVEN FUNCTIONALITY CAN BE TAKEN. THE USER MUST ASSUME THE ENTIRE RISK OF USING THIS SOFTWARE.

[http_www.codeproject.com_Articles_38553_Task-Scheduler]: http://www.codeproject.com/Articles/38553/Task-Scheduler
[Download demo project_- 12.46 KB]: http://www.codeproject.com/KB/cs/Another_TaskScheduler/TaskScheduler_1.2_DEMO.zip
[Download source - 49.97 KB]: http://www.codeproject.com/KB/cs/Another_TaskScheduler/TaskScheduler_1.2_src.zip
[Image 1]: 
[Another_TaskScheduler_TriggerSettings.jpg]: /images/20220805/a383c9611358479bbd35bcc87fe34172.png