iOS 文字下划线

给UILabel添加下划线

 NSMutableAttributedString *content = [[NSMutableAttributedString alloc]initWithString:text];
    NSRange contentRange = {0,[content length]};
    [content addAttribute:NSUnderlineStyleAttributeName value:[NSNumber numberWithInteger:NSUnderlineStyleSingle] range:contentRange];
    
    [_titleLabel setAttributedText:content];