用到了，記錄下

NSArray * labelArray = @[@"天蒼蒼",@"明日依山盡",@"老夫聊發少年狂",@"左牽黃右擒蒼錦帽貂裘哈哈哈"];

for (int i = 0; i < labelArray.count; i++) {
    UILabel  *label = [UILabel new];

    label.font = [UIFont systemFontOfSize:11];
    label.text = labelArray[i];
    [self.view addSubview:label];
    CGSize size = [labelArray[i] sizeWithAttributes:@{NSFontAttributeName: [UIFont systemFontOfSize:11.0f]}];
    NSLog(@"==第%d個===%f===%f",i,size.width,size.height);
}

控制臺Log

沒換行高度計算一樣的