//计算实际frame大小，并将label的frame变成实际大小    CGSize size01 = [ssizeWithFont:[UIFontsystemFontOfSize:15.0f]constrainedToSize:sizelineBreakMode:NSLineBreakByWordWrapping];    [label setFrame:CGRectMake(10,50, size01.width, size01.height)];

 UILabel *label = [[UILabel alloc] initWithFrame:CGRectMake(0, 0, 100, 46)];    NSString *str=@"发恶无法奶奶问服务就啃发觉我看能否尽快稳罚款金额为你放假";    label.text=str;    UIFont *font=[UIFont systemFontOfSize:15];    label.font=font;        //拆行    label.lineBreakMode=NSLineBreakByWordWrapping;    //设置多行    [label setNumberOfLines:0];        //设置最大尺寸的宽和高    CGSize size=CGSizeMake(100, 1000);    //获取当前字体    NSDictionary *dict=@{NSFontAttributeName: [UIFont systemFontOfSize:15]};    CGSize authSize=[str boundingRectWithSize:size                                       options:NSStringDrawingUsesLineFragmentOrigin                                    attributes:dict                                       context:nil].size;    label.frame=CGRectMake(20, 70, authSize.width, authSize.height);    [self.view addSubview:label];