iOS UILabel显示html内容

// 将html内容转化为attributedString
NSString * htmlString = @"<font color='#4085de'> worldcpp </font> <font color='#333333'>来啦 ~</font> 来啦🎉";  
NSDictionary *options = @{ NSDocumentTypeDocumentAttribute: NSHTMLTextDocumentType };
NSMutableAttributedString * attributeString = [[NSMutableAttributedString alloc] initWithData:[htmlString 
dataUsingEncoding:NSUnicodeStringEncoding] 
options:options 
documentAttributes:nil error:nil];
// 富文本字体、颜色等设置
NSDictionary *attributes = @{ NSFontAttributeName: [UIFont systemFontOfSize:16] }
[attributeString addAttributes: attributes, range: NSMageRange(location: 0, length: attributeString.length)];

self.userComeLabel.attributedText = attributeString;
// 计算富文本的size
CGSize textSize = [attributeString boundingRectWithSize:CGSizeMake(CGFLOAT_MAX, 26)
 options:NSStringDrawingUsesFontLeading 
context:nil].size;
CGFloat userComeLabelWidth = textSize.width;