NSMutableAttributedString 富文本的使用

//富文本的使用
    UILabel *testLabel = [[UILabel alloc]initWithFrame:CGRectMake(, , , )];

    testLabel.backgroundColor = [UIColor lightGrayColor];

    testLabel.textAlignment = NSTextAlignmentCenter;

    NSMutableAttributedString *AttributedStr = [[NSMutableAttributedString alloc]initWithString:@"今天天气不错呀"];

    [AttributedStr addAttribute:NSFontAttributeName

                          value:[UIFont systemFontOfSize:25.0]

                          range:NSMakeRange(, )];

    [AttributedStr addAttribute:NSForegroundColorAttributeName

                          value:[UIColor redColor]

                          range:NSMakeRange(, )];

    testLabel.attributedText = AttributedStr;

    [self.view addSubview:testLabel];