只能在iOS7以后运行
NSString * htmlString = @" <html><body>Some html string \n<font size=\"13\" color=\"red\">This is some text!</font></body>";
NSAttributedString * attrStr = [[NSAttributedString alloc] initWithData:[htmlString dataUsingEncoding:NSUnicodeStringEncoding] options:@{ NSDocumentTypeDocumentAttribute: NSHTMLTextDocumentType } documentAttributes:nil error:nil];
UILabel * myLabel = [[UILabel alloc] initWithFrame:self.view.bounds]; myLabel.attributedText = attrStr; [self.view addSubview:myLabel];
