Google drive api 如何从Google Drive asp.net下载文件

我正在尝试从谷歌硬盘下载文件，下面是我的代码

private static IAuthenticator CreateAuthenticator()
{
    var provider = new NativeApplicationClient(GoogleAuthenticationServer.Description);
    provider.ClientIdentifier = ClientCredentials.CLIENT_ID;
    provider.ClientSecret = ClientCredentials.CLIENT_SECRET;
    return new OAuth2Authenticator<NativeApplicationClient>(provider, GetAuthorization);
}


public static System.IO.Stream DownloadFile(
        IAuthenticator authenticator, Google.Apis.Drive.v2.Data.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;
        }
    }

它显示此流不支持查找操作

错误在哪里

---

谢谢您……

如果您只是想下载文件，则无需查找该文件。您应该做的只是读取流，即通过DownloadFile API方法读取流并将其传递给浏览器。我已通过以下代码启用它：

public FileResult DownloadFile(string fileId)
    {
        DriveService service = Session["service"] as DriveService;
        Google.Apis.Drive.v2.Data.File file = service.Files.Get(fileId).Fetch(); 
        System.IO.Stream data = new GDriveRepository(Utils.ReturnIAuth((GoogleAuthenticator)Session["Gauthenticator"])).DownloadFile(file.DownloadUrl);

        return File(data, System.Net.Mime.MediaTypeNames.Application.Octet, file.Title);
    }

public FileResult DownloadFile(string fileId)
    {
        DriveService service = Session["service"] as DriveService;
        Google.Apis.Drive.v2.Data.File file = service.Files.Get(fileId).Fetch(); 
        System.IO.Stream data = new GDriveRepository(Utils.ReturnIAuth((GoogleAuthenticator)Session["Gauthenticator"])).DownloadFile(file.DownloadUrl);

        return File(data, System.Net.Mime.MediaTypeNames.Application.Octet, file.Title);
    }