IOS 优惠价格添加删除线

做电商类的app时，会经常遇到打折的时候，而网上打折价格的lable的删除线千篇一律，其实IOS本自带的就有删除闲的功能，Demo如下

UILabel *numberPrice=[[UILabel alloc]init];

numberPrice.text=@"199.0元";

numberPrice.textColor=[UIColor grayColor];

NSUInteger length = [numberPrice.text length];

//添加删除线

NSMutableAttributedString *attri = [[NSMutableAttributedString alloc] initWithString:numberPrice.text];

[attri addAttribute:NSStrikethroughStyleAttributeName value:@(NSUnderlinePatternSolid | NSUnderlineStyleSingle) range:NSMakeRange(2, length-2)];

[attri addAttribute:NSStrikethroughColorAttributeName value:[UIColor grayColor] range:NSMakeRange(2, length-2)];

[numberPrice setAttributedText:attri];