如何使用vb.net在Google Drive上上传文件？

Question

我需要帮助上传文件到Google Drive。一切工作正常，但在第一次试验中出现错误。在调试期间，在 request.upload 光标不要等待（等待文件上传），跳到下一行。Dim responsefile As New Data.File 而我一无所获 request.ResponseBody. 在这之后，我运行的函数光标实际上是等待在 request.upload 并成功上传文件。我不知道到底发生了什么。我检查了每次的数据，都是一样的。

Public Async Function UploadFile3(service As DriveService, FilePath As String) As Tasks.Task(Of Data.File)

        If service3.ApplicationName <> "netGDriveApi" Then CreateService()
            If IO.File.Exists(FilePath) Then
                Dim body As New Data.File()
                body.Name = IO.Path.GetFileName(FilePath)
                body.Description = "BackUP file"
                body.MimeType = "application/octet-stream"
                'body.FileExtension = ".bak"



                '-------------------------------------------------UPLOAD FILE PROCESS-------------------------------------------------------------

                Dim byteArray As Byte() = IO.File.ReadAllBytes(FilePath)
                Dim stream As New IO.MemoryStream(byteArray)
                Try
                    Dim request As FilesResource.CreateMediaUpload = service.Files.Create(body, stream, body.MimeType)
                    Await request.UploadAsync() 'Cursor skips first time here and dont wait for response.
                    Dim responsefile As New Data.File 'Cursor waits from the above step to here till the file uploaded.


                    responsefile = request.ResponseBody

                    If IsNothing(responsefile) Then
                        MessageBox.Show("Try Again")
                    Else
                        MessageBox.Show(responsefile.Id.ToString)
                    End If

                Catch e As Exception
                    MessageBox.Show("An error occurred: " + e.Message)
                    Return Nothing
                End Try

            Else
                MessageBox.Show("FILE DOES NOT EXISTS." + FilePath)
                Return Nothing
            End If
End Function

Answer 1

request.UploadAsync() 返回一个 Task(Of IUploadProgress). 至少，你应该检查这项任务的结果。它可能会给你提供问题原因的线索。

例如，在调试的时候，你可以做如下的事情。

Try
    Dim request As FilesResource.CreateMediaUpload = service.Files.Create(body, stream, body.MimeType)

    Dim Upload As IUploadProgress = Await request.UploadAsync() 'Cursor skips first time here and dont wait for response.

    If Upload.Status <> UploadStatus.Completed Then
        Dim ex As Exception = Upload.Exception
        MessageBox.Show(ex.Message, "UploadAsync Error", MessageBoxButtons.OK, MessageBoxIcon.Error)
        Return Nothing
    Else
        MessageBox.Show(Upload.Status.ToString, "Upload Status:")
    End If

    Dim responsefile As New Data.File 'Cursor waits from the above step to here till the file uploaded.
    responsefile = request.ResponseBody

总是检查方法返回的信息，并在生产代码中使用这些信息。

Answer 2

这一行 Dim request As FilesResource.CreateMediaUpload = service.Files.Create(body, stream, body.MimeType). 问题就在这里。感谢@stevec给我指导错误。驱动器服务是service3，在上面一行中，它只是写了 service.Files.Create. 所以实际的整改答案是 Dim request As FilesResource.CreateMediaUpload = service3.Files.Create(body, stream, body.MimeType)