iOS UILabel 显示 html

Myth丶恋晨 2022-05-25 12:59 279阅读 0赞

效果图：

![20180515111118316][]

实现：

#import "ViewController.h"
    
    @interface ViewController ()
    
    @end
    
    @implementation ViewController
    
    - (void)viewDidLoad {
        [super viewDidLoad];
        
        NSString * htmlString = @"<html><body>PM<sub>2.5<sub> <font size=\"13\" color=\"red\">hello world!</font> </body></html>";
        
        UILabel * label = [[UILabel alloc] initWithFrame:self.view.bounds];
        
        label.attributedText = [self strToAttriWithStr:htmlString];
        [self.view addSubview:label];
        
        CGRect rect = label.frame;
        rect.size.height = [self getAttriHeightWithLabel:label width:self.view.bounds.size.width];
        label.frame = rect;
        
    }
    
    /**
     *  富文本转html字符串
     */
    - (NSString *)attriToStrWithAttri:(NSAttributedString *)attri{
        NSDictionary *tempDic = @{NSDocumentTypeDocumentAttribute:NSHTMLTextDocumentType,
                                  NSCharacterEncodingDocumentAttribute:[NSNumber numberWithInt:NSUTF8StringEncoding]};
        
        NSData *htmlData = [attri dataFromRange:NSMakeRange(0, attri.length)
                             documentAttributes:tempDic
                                          error:nil];
        
        return [[NSString alloc] initWithData:htmlData
                                     encoding:NSUTF8StringEncoding];
    }
    
    /**
     *  字符串转富文本
     */
    - (NSAttributedString *)strToAttriWithStr:(NSString *)htmlStr{
        return [[NSAttributedString alloc] initWithData:[htmlStr dataUsingEncoding:NSUnicodeStringEncoding]
                                                options:@{NSDocumentTypeDocumentAttribute:NSHTMLTextDocumentType}
                                     documentAttributes:nil
                                                  error:nil];
    }
    
    /**
     *获得富文本的高度
     **/
    -(CGFloat)getAttriHeightWithLabel:(UILabel *)label width:(CGFloat)width {
        CGFloat height = [label.attributedText boundingRectWithSize:CGSizeMake(width, CGFLOAT_MAX) options:NSStringDrawingUsesLineFragmentOrigin context:nil].size.height;//针对富文本
        return height;
    }
    
    
    @end

[20180515111118316]: /images/20220525/ca6b3a03ad134588baed8b0d7f28ff84.png