VB.Net Webclient Upload Hanging

Question

I have multiple files to upload (to FTP server) using this code:

    Private Sub UploadFile(ByVal local As String)
    If wc.IsBusy = True Then Throw New Exception("An upload is already ongoing!")

    wc.Credentials = New NetworkCredential(usr.ToString, pass.ToString) 'Set the credentials.
    'total_dl_size = GetDownloadSize(url) 'Get the size of the current file.

    Try
        Dim FileName As String = Path.GetFileName(local) 'Get the current file's name.
        AppendWarning("Uploading " & FileName & "...   ") 'Download notice.
        wc.UploadFileAsync(New Uri(info_srv & local), Path.Combine(mc_dir, local)) 'Download the file to the desktop (use your own path here).
    Catch ex As Exception
        AppendWarning("-ERR: Could not download file: " & local & ControlChars.NewLine)
    End Try
End Sub
Private Sub AppendWarning(ByVal Text As String)
    If tb_warnings.InvokeRequired Then
        tb_warnings.Invoke(Sub() tb_warnings.AppendText(Text))
    Else
        tb_warnings.AppendText(Text)
    End If

End Sub

Private Sub wc_UploadProgressChanged(sender As Object, e As System.Net.UploadProgressChangedEventArgs) Handles wc.UploadProgressChanged
    total_ul = e.BytesSent
    Dim Progress As Integer = CType(Math.Round((baseline + total_ul) * 100) / total_ul_size, Integer)
    If ProgressBar1.InvokeRequired Then
        ProgressBar1.Invoke(Sub()

                                If Progress > 100 Then Progress = 100
                                If Progress < 0 Then Progress = 0
                                ProgressBar1.Value = Progress
                            End Sub)
    Else
        If Progress > 100 Then Progress = 100
        If Progress < 0 Then Progress = 0
        ProgressBar1.Value = Progress
    End If
    If lbl_progress.InvokeRequired Then
        lbl_progress.Invoke(Sub() lbl_progress.Text = ((total_ul + baseline) / 1024).ToString("N0") & " KB / " & (total_ul_size / 1024).ToString("N0") & " KB")
    Else
        lbl_progress.Text = ((total_ul + baseline) / 1024).ToString("N0") & " KB / " & (total_ul_size / 1024).ToString("N0") & " KB | " & Progress.ToString & "%"
    End If

End Sub
Private Sub wc_uploadFileCompleted(sender As Object, e As System.ComponentModel.AsyncCompletedEventArgs) Handles wc.UploadDataCompleted
    If e.Cancelled Then
        MessageBox.Show(e.Cancelled)

    ElseIf Not e.Error Is Nothing Then
        MessageBox.Show(e.Error.Message)

    Else
        If files.Count > 0 Then
            AppendWarning("Upload Complete!" & ControlChars.NewLine)
            baseline = baseline + total_ul
            Dim file As String = files.Dequeue()
            MsgBox(file)
            UploadFile(file) 'Download the next file.
        Else
            AppendWarning("All Uploads Finished!" & ControlChars.NewLine)
        End If

    End If

However, using my two test files, it always stops at what would otherwise be the end of the first file I've given it, and doesn't go onto the second one.

However, I have an FTP client connected to this same server, and when I refresh I can see (at least for the first file) the data is being properly uploaded.

Any suggestions as to what's going wrong here?

Edit, log: http://pastebin.com/kqG28NGH

Thank you for any assistance!

Answer 1

This works for me...I tried to mimic what I think is in your form. I tested with a queue of 8 files ranging from 150K to 400K each. I couldn't quite work out what you were trying to do with the progress bar. Mine fills for each file and resets for the next, finishing empty with the last call to DoUpload where there are no more files. Hopefully, this will help.

Imports System.IO
Imports System.Net

Public Class Form1
    Const info_srv As String = "ftp://example.com/SomeFolder/"
    Const usr As String = ""
    Const pass As String = ""

    Const mc_dir As String = "D:\Source\Folder"

    Private WithEvents wc As New Net.WebClient

    ' Contains file names only, no paths
    Private Files As New Queue(Of String)

    Private Sub Button1_Click(sender As Object, e As EventArgs) _
        Handles Button1.Click

        wc.Credentials = New NetworkCredential(usr, pass)

        ' Put the work in a task so UI is responsive
        Task.Run(Sub() DoUpload())
    End Sub

    Private Sub DoUpload()
        ShowProgress("", 0)

        If Files.Count > 0 Then
            Dim local As String = Files.Dequeue
            Dim FileName As String = Path.Combine(mc_dir, local)

            AppendWarning("Uploading " & FileName & "...   ")

            Try
                wc.UploadFileAsync(New Uri(info_srv & local), FileName)
            Catch ex As Exception
                AppendWarning("-ERR: Could not upload file: " & local & Environment.NewLine)
            End Try
        Else
            AppendWarning("All Uploads Finished!" & Environment.NewLine)
        End If
    End Sub

    Private Sub wc_UploadProgressChanged(sender As Object, e As UploadProgressChangedEventArgs) _
        Handles wc.UploadProgressChanged

        ' Do not use e.ProgressPercentage - it's inaccurate by half by design per Microsoft
        With String.Format("{0} KB / {1} KB", Int(e.BytesSent / 1024).ToString("N0"), Int(e.TotalBytesToSend / 1024).ToString("N0"))
            ShowProgress(.ToString, Int(e.BytesSent / e.TotalBytesToSend * 100))
        End With

    End Sub

    Private Sub wc_UploadFileCompleted(sender As Object, e As UploadFileCompletedEventArgs) _
        Handles wc.UploadFileCompleted

        Select Case True
            Case e.Cancelled
                MessageBox.Show("Cancelled")
            Case e.Error IsNot Nothing
                MessageBox.Show(e.Error.Message)
            Case Else
                AppendWarning("Upload Complete!" & Environment.NewLine)

                ' I needed this just so I could see it work, otherwise too fast
                Threading.Thread.Sleep(500)

                DoUpload()
        End Select
    End Sub

    Private Sub AppendWarning(ByVal Text As String)
        If Me.InvokeRequired Then
            Me.Invoke(Sub() AppendWarning(Text))
        Else
            tb_warnings.AppendText(Text)
        End If
    End Sub

    Private Sub ShowProgress(LabelText As String, Progress As Integer)
        If Me.InvokeRequired Then
            Me.Invoke(Sub() ShowProgress(LabelText, Progress))
        Else
            Me.lbl_progress.Text = LabelText
            Me.lbl_progress.Refresh()

            Me.ProgressBar1.Value = Progress
            Me.ProgressBar1.Refresh()
        End If
    End Sub
End Class

Answer 2

For posterity:

Check your network trace settings in the VB config. I used a really verbose catch-all config I found to do the trace, but it seems the overhead was killing the upload. I've since found a much leaner focus-on-ftp set of xml to modify this and the files now upload properly. Thank you everyone!