iOS开发改变字符串中指定字符颜色,大小等等

    NSString *strJTGZ = [NSString stringWithFormat:@"交通管制%d处 ",[jtgz intValue]];
        NSMutableAttributedString *attributedStr = [[NSMutableAttributedString alloc]initWithString:strJTGZ];
        [attributedStr addAttribute:NSForegroundColorAttributeName value:[UIColor redColor] range:NSMakeRange(4,  [self getRedNumberLength:[jtgz intValue]])];
        [mutableStr appendAttributedString:attributedStr];