小记

1.添加划线(对象方法), NSString的分类:

- (NSMutableAttributedString *)addCancelLine {
    NSMutableAttributedString *attri = [[NSMutableAttributedString alloc] initWithString:self];
    [attri addAttributes:@{NSStrikethroughColorAttributeName : [UIColor redColor], NSStrikethroughStyleAttributeName : [NSNumber numberWithInteger:NSUnderlineStyleSingle]} range:NSMakeRange(0, self.length)];
    return attri;
}
label.attributedText = [字符串 addCancelLine];

2. 去除字符串尾部的0 例如:$9.900

   - (NSString *)cleanDecimalPoint {
          NSString *newString = nil;
          NSUInteger offset = self.length - 1;
          while (offset > 0) {
          newString = [self substringWithRange:NSMakeRange(offset, 1)]; //从字符串最后一位开始取一位
          if ([newString isEqualToString:@"0"] || [newString isEqualToString:@"."]) {
                  offset--;
              } else {
                  break;
              }
      }
      return [self substringToIndex:(offset + 1)];
   }

3.数组中的内容倒数排列后产生新的装有倒序后的数组

NSArray *reversedArray = [[_contentArray reverseObjectEnumerator] allObjects];