iOS--- 设置label button的文字显示几种颜色 ,加下划线

    UILabel *label=[[UILabel alloc] initWithFrame:CGRectMake(0,60, 150, 30)];

    label.text=@"你好helloworld";

    label.backgroundColor=[UIColor lightGrayColor];

    NSMutableAttributedString *attriString=[[NSMutableAttributedString alloc] initWithString:label.text];

    NSRange range1=NSMakeRange(0,3);//设置从第1个到底4个显示红色 location是0 长度是3

    NSRange range2=NSMakeRange(4,2);//设置第5和第6两个显示绿色  Location是4 长度是2

    NSLog(@"label.text length is %d ",label.text.length);

    //第一个字

    [attriString addAttribute:NSForegroundColorAttributeName value:[UIColor redColor] range:range1];

    [attriString addAttribute:NSForegroundColorAttributeName value:[UIColor greenColor]range:range2];

    label.attributedText=attriString;

    [self.view addSubview:label];

    

    

    UIButton *button = [[UIButton alloc] init];

    button.frame=CGRectMake(0,120, 150, 50);

    [button setTitle:@"你好视界"forState:UIControlStateNormal];

    [button setBackgroundColor:[UIColor lightGrayColor]];

    NSMutableAttributedString *btnAttStr=[[NSMutableAttributedString alloc] initWithString:button.titleLabel.text];

    NSRange btnRange=NSMakeRange(0,2);//设置你好是绿色

    NSRange btnR=NSMakeRange(2,2); //设置视界是红色

    [btnAttStr addAttribute:NSForegroundColorAttributeName value:[UIColor greenColor]range:btnRange];

    [btnAttStr addAttribute:NSForegroundColorAttributeName value:[UIColor redColor] range:btnR];

    [button setAttributedTitle:btnAttStr forState:UIControlStateNormal];

    [self.view addSubview:button];

    [_tiankuanBtn setTitle:@"注册表示已同意《隐私条款以及服务协议》" forState:UIControlStateNormal];

    NSMutableAttributedString *btnAttStr=[[NSMutableAttributedString alloc] initWithString:_tiankuanBtn.titleLabel.text];

    NSRange btnRange=NSMakeRange(0,7);//设置你好是绿色

    NSRange btnR=NSMakeRange(7,12); //设置视界是红色

    [btnAttStr addAttribute:NSForegroundColorAttributeName value:[UIColor greenColor]range:btnRange];

    [btnAttStr addAttribute:NSForegroundColorAttributeName value:[UIColor redColor] range:btnR];

    [_tiankuanBtn setAttributedTitle:btnAttStr forState:UIControlStateNormal];

    NSMutableAttributedString *str = [[NSMutableAttributedString alloc] initWithString:@"注册表示已同意《隐私条款以及服务协议》"];

    NSRange strRange = {7,12};

    [str addAttribute:NSUnderlineStyleAttributeName value:[NSNumber numberWithInteger:NSUnderlineStyleSingle] range:strRange];

    [_tiankuanBtn setAttributedTitle:str forState:UIControlStateNormal];