下划线

NSMutableAttributedString *str = [[NSMutableAttributedString alloc] initWithString:

@"4、本活动最终解释权归量子排毒垫所有，如有其他疑问请咨询官方客服0592-12345678；"];

[str addAttribute:NSForegroundColorAttributeName value:

[UIColor colorWithRed:17/255.0 green:17/255.0 blue:17/255.0 alpha:1] range:NSMakeRange(0,32)];

[str addAttribute:NSForegroundColorAttributeName value:

[UIColor colorWithRed:12/255.0 green:190/255.0 blue:61/255.0 alpha:1] range:NSMakeRange(32,13)];

[str addAttribute:NSUnderlineStyleAttributeName value:

[NSNumber numberWithInteger:NSUnderlineStyleSingle] range:NSMakeRange(32, 13)]; // 下划线类型

_lb.attributedText = str;