为什么当检查上传到youtube处理状态的视频文件时，结果总是为空

这是我用来上传视频文件到youtube的上传方法。

static Video video = null;
        private void UploadVideo(string FileName, string VideoTitle, string VideoDescription)
        {
            try
            {
                UserCredential credential;
                using (FileStream stream = new FileStream(@"D:'C-Sharp'Youtube-Manager'Youtube-Manager'Youtube-Manager'bin'Debug'client_secrets.json", FileMode.Open, FileAccess.Read))
                {
                    credential = GoogleWebAuthorizationBroker.AuthorizeAsync(
                        GoogleClientSecrets.Load(stream).Secrets,
                        new[] { YouTubeService.Scope.Youtube, YouTubeService.Scope.YoutubeUpload },
                        "user",
                        CancellationToken.None,
                        new FileDataStore("YouTube.Auth.Store")).Result;
                }
                var youtubeService = new YouTubeService(new BaseClientService.Initializer()
                {
                    HttpClientInitializer = credential,
                    ApplicationName = Assembly.GetExecutingAssembly().GetName().Name
                });
                video = new Video();
                video.Snippet = new VideoSnippet();
                video.Snippet.Title = VideoTitle;
                video.Snippet.Description = VideoDescription;
                video.Snippet.Tags = new string[] { "tag1", "tag2" };
                video.Status = new VideoStatus();
                video.Status.PrivacyStatus = "public";
                using (var fileStream = new FileStream(FileName, FileMode.Open))
                {
                    const int KB = 0x400;
                    var minimumChunkSize = 256 * KB;
                    var videosInsertRequest = youtubeService.Videos.Insert(video,
                        "snippet,status", fileStream, "video/*");
                    videosInsertRequest.ProgressChanged +=
                        videosInsertRequest_ProgressChanged;
                    videosInsertRequest.ResponseReceived +=
                        videosInsertRequest_ResponseReceived;
                    // The default chunk size is 10MB, here will use 1MB.
                    videosInsertRequest.ChunkSize = minimumChunkSize * 3;
                    dt = DateTime.Now;
                    videosInsertRequest.Upload();
                }
            }
            catch (Exception errors)
            {
                string errorss = errors.ToString();
            }
        }

在这个事件中，我创建了一个计时器:

    Video objects = null;
    private void videosInsertRequest_ResponseReceived(Video obj)
    {
        System.Timers.Timer aTimer;
        aTimer = new System.Timers.Timer();
        aTimer.Elapsed += aTimer_Elapsed;
        aTimer.Interval = 10000;
        aTimer.Enabled = true;
        objects = obj;
    }

然后在Elapsed事件中检查视频文件处理状态:

void aTimer_Elapsed(object sender, System.Timers.ElapsedEventArgs e)
        {
            fff = objects.ProcessingDetails.ProcessingStatus;
        }

但是ProcessingDetails和ProcessingStatus总是null。即使我浏览到youtube，看到我的视频文件已经在线处理，它在我的程序中仍然是空的。

我想每隔10秒实时检查一次，看看视频是否仍处于处理模式，以及处理模式何时结束。

 while (true)
 {
       string status = video.Status.UploadStatus;
 }