iOS label添加删除线

 NSString * textStr = [NSString stringWithFormat:@"原价:￥%.2f",model.par_value];

  NSUInteger length = textStr.length;

  NSMutableAttributedString *attri = [[NSMutableAttributedString alloc] initWithString:[NSString stringWithFormat:@"原价:￥%.2f",model.par_value]];

  [attri addAttribute:NSStrikethroughStyleAttributeName value:@(NSUnderlinePatternSolid | NSUnderlineStyleSingle) range:NSMakeRange(0, length)];

  [attri addAttribute:NSStrikethroughColorAttributeName value:[UIColor grayColor] range:NSMakeRange(0, length)];

  [self.oldPriceLabel setAttributedText:attri];