好的代码片段

////修改字体颜色

- (NSMutableAttributedString *)changeNumberColorWithString:(NSString *)content {

    NSArray * number = @[@"0",@"1",@"2",@"3",@"4",@"5",@"6",@"7",@"8",@"9", @"元"];

    NSMutableAttributedString *attributeString  = [[NSMutableAttributedString alloc]initWithString:content];

    for (int i = 0; i < content.length; i++) {

        NSString * str = [content substringWithRange:NSMakeRange(i, 1)];

        if ([number containsObject:str]) {

            [attributeString addAttribute:NSForegroundColorAttributeName value:FOCUSCOLOR range:NSMakeRange(i, 1)];

        }

    }

    return attributeString;

}