UILabel *label = [[UILabel alloc] init];

    label.frame = CGRectMake(, , , );

    label.backgroundColor = [UIColor yellowColor];

    NSString *name = @"David贾永强";

    float money = 2.0;

    NSString *contentStr = [NSString stringWithFormat:@"%@ 五分钟前薅取 %.2f元 羊毛",name,money];

    NSMutableAttributedString *str = [[NSMutableAttributedString alloc]initWithString:contentStr];

    [str addAttribute:NSFontAttributeName value:[UIFont systemFontOfSize:] range:NSMakeRange(, contentStr.length)];

    //名字

    NSRange nameRang = NSMakeRange(, name.length);

    [str addAttribute:NSForegroundColorAttributeName value:[UIColor greenColor] range:nameRang];

    [str addAttribute:NSFontAttributeName value:[UIFont systemFontOfSize:] range:nameRang];

    //钱数

    NSRange moneyRang = NSMakeRange(name.length + , );

    [str addAttribute:NSForegroundColorAttributeName value:[UIColor redColor] range:moneyRang];

    [str addAttribute:NSFontAttributeName value:[UIFont systemFontOfSize:] range:moneyRang];

    label.attributedText = str;

    [label sizeToFit];

    [self.view addSubview:label];

 //进行动态获取高度和宽度。必须用这个NSDictionary，不能用NSMutableDictionary这个。

    NSString *str            = @"自动计算高度，然后换行,自动计算高度，然后换行,自动计算高度，然后换行,自动计算高度，然后换行,自动计算高度，然后换行,自动计算高度，然后换行,自动计算高度，然后换行,自动计算高度，然后换行,自动计算高度，然后换行,结束";

    UIFont *font             = [UIFont systemFontOfSize:15.0f];

    NSDictionary *attributes = @{ NSFontAttributeName: font };

    CGSize size              = [str sizeWithAttributes:attributes];

    UILabel *label           = [[UILabel alloc] init];

    label.frame              = CGRectMake(, , size.width, size.height);

    label.text               = str;

    label.font               = font;

    label.backgroundColor    = [UIColor orangeColor];

    [self.view addSubview:label];

    // 自动计算高度，然后换行

    label.lineBreakMode      = NSLineBreakByWordWrapping;

    label.numberOfLines      = ;

    //boundSize,决定label的宽度. 设为屏幕宽度-100. 也可以设置固定的宽度

    CGSize boundSize         = CGSizeMake([UIScreen mainScreen].bounds.size.width-, MAXFLOAT);

    CGSize  brSize           = [str boundingRectWithSize:boundSize options:NSStringDrawingUsesLineFragmentOrigin | NSStringDrawingUsesFontLeading attributes:attributes context:nil].size;

    label.frame              = CGRectMake(, , brSize.width, brSize.height);

　　//UILabel 的高度会根据字体自身,大小,label的宽度 自动计算.

    UILabel *_label = [[UILabel alloc] initWithFrame:CGRectMake(, , , )];

    _label.backgroundColor = [UIColor greenColor];

    _label.font = [UIFont systemFontOfSize:];

    _label.text = @"自动计算高度，然后换行自动计算高度，然后换行,自动计算高度，然后换行自动计算高度，然后换行,结束";

    _label.numberOfLines = ;

    [_label sizeToFit];

    [self.view addSubview:_label];