如何在安装了WPF的应用程序中从谷歌驱动器下载文件

本文关键字：谷歌 驱动器 文件 下载 应用程序 安装 WPF | 更新日期: 2023-09-27 18:10:01

我正在开发WPF应用程序，并且在此我正在实现具有上传和下载功能的Google Drive API。上传工作正常，但我在下载文件时遇到了问题。我查看了谷歌文档中的代码https://developers.google.com/drive/web/manage-downloads

 public static System.IO.Stream DownloadFile(IAuthenticator authenticator, File file) 
 {
   if (!String.IsNullOrEmpty(file.DownloadUrl)) 
   {
     try {
       HttpWebRequest request = (HttpWebRequest)WebRequest.Create(new Uri(file.DownloadUrl));
       authenticator.ApplyAuthenticationToRequest(request);
       HttpWebResponse response = (HttpWebResponse) request.GetResponse();
       if (response.StatusCode == HttpStatusCode.OK) 
       {
          return response.GetResponseStream();
       }
       else
       {
          Console.WriteLine("An error occurred: " + response.StatusDescription);
          return null;
       }
    }
    catch (Exception e) 
    {
      Console.WriteLine("An error occurred: " + e.Message);
      return null;
    }
  }
  else
  {
    // The file doesn't have any content stored on Drive.
    return null;
  }

}

但是根据这份文件"https://code.google.com/p/google-api-dotnet-client/source/browse/Src/GoogleApis/Apis/Authentication/IAuthenticator.cs?r=e6585033994bfb3a24d4c140db834cb14b9738b2"它显示"IAuthenticator不再受支持"，因此上面的代码不起作用。

我尝试使用UserCredential，但它抛出"远程服务器返回一个错误:(401)Unauthorized."。

所以请提供相同的代码在WPF应用程序或我如何从谷歌驱动器下载任何类型的文件。

如何在安装了WPF的应用程序中从谷歌驱动器下载文件

根据文档，您需要下载新的google . api . auth内核包。之后，执行以下步骤

    访问Google api控制台
  • 如果这是你的第一次，点击"创建项目…"
  • 否则，点击左上角"Google api"标志下的下拉菜单，然后点击"其他项目"
    • 下的"创建…"
  • 点击"API Access"，然后点击"Create an OAuth 2.0 Client ID…"
  • 输入产品名称，点击"下一步"。
  • 选择"Installed application"，点击"Create client ID"。
  • 在新创建的"客户端ID for installed applications"中，将客户端ID和客户端秘密复制到adsensessample .cs文件中。
  • 为你的项目激活驱动API

参考Google api Client Library for .NET

完成这些步骤后，您可以使用以下代码下载文件

private async Task Run()
    {
        GoogleWebAuthorizationBroker.Folder = "Drive.Sample";
        UserCredential credential;
        using (var stream = new System.IO.FileStream("client_secrets.json",
            System.IO.FileMode.Open, System.IO.FileAccess.Read))
        {
            credential = await GoogleWebAuthorizationBroker.AuthorizeAsync(
                GoogleClientSecrets.Load(stream).Secrets, Scopes, "user", CancellationToken.None);
        }
        // Create the service.
        var service = new DriveService(new BaseClientService.Initializer()
        {
            HttpClientInitializer = credential,
            ApplicationName = "Drive API Sample",
        });
        await UploadFileAsync(service);
        // uploaded succeeded
        Console.WriteLine("'"{0}'" was uploaded successfully", uploadedFile.Title);
        await DownloadFile(service, uploadedFile.DownloadUrl);
        await DeleteFile(service, uploadedFile);
    }

    private async Task DownloadFile(DriveService service, string url)
    {
        var downloader = new MediaDownloader(service);
        downloader.ChunkSize = DownloadChunkSize;
        // add a delegate for the progress changed event for writing to console on changes
        downloader.ProgressChanged += Download_ProgressChanged;
        // figure out the right file type base on UploadFileName extension
        var lastDot = UploadFileName.LastIndexOf('.');
        var fileName = DownloadDirectoryName + @"'Download" +
            (lastDot != -1 ? "." + UploadFileName.Substring(lastDot + 1) : "");
        using (var fileStream = new System.IO.FileStream(fileName,
            System.IO.FileMode.Create, System.IO.FileAccess.Write))
        {
            var progress = await downloader.DownloadAsync(url, fileStream);
            if (progress.Status == DownloadStatus.Completed)
            {
                Console.WriteLine(fileName + " was downloaded successfully");
            }
            else
            {
                Console.WriteLine("Download {0} was interpreted in the middle. Only {1} were downloaded. ",
                    fileName, progress.BytesDownloaded);
            }
        }
    }

您可以下载google drive api的示例应用程序

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