I am coding an FTP program, the downloading/uploading happens in a seperate thread. The problem is now how to pause/resume the download (even on servers that don't support file resume), an easy/working way is to pause/resume the working thread with thread.suspend but it tells me that this function is obsolete.

Is there a simmilar method to achieve this? I've tried looking up Mutexes, Monitor, Event, Semaphore stuff but that would only allow me to pause the file transfer after the file is done.

So the code that 'lives' in the thread that I want to suspend looks something like

Private Sub StartUpload(ByVal allFiles As Hashtable)
        For Each singleFile As String In allFiles.Keys
                ftpClient.UploadFile(singleFile, allFiles.Item(singleFile), False)
            Catch ex As Exception
                Exit For
            End Try
        allFiles = Nothing
    End Sub

Function get called as following:

UploadThread = New Threading.Thread(AddressOf StartUpload)

So UploadThread.suspend() / resume works perfectly, but I can't really release this if these functions get removed in future releases of .net

Any help is appreciated


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I don't believe that support for these methods will be removed in any future release, for backwards compatability. The reason for it being marked as obsolete is because when suspending a thread, you cannot determine where in the method the thread suspends at. Instead, you should generally use a boolean variable, and have the method check at certain points the value of the variable, and suspend the thread using a while loop or something.

Almost forgot to mark it as solved d'oh

Actually after days of trying i figured out that Thread.Suspend is exactlly what i shouldn't do o.O
When i suspend the FTP Upload it works perfect for exact the time until the FTP server timeouts and disconnect. If i then want to resume my Upload it fails ofc.
Anyway it seems i still have two possibilities:
1. pausing the transfer after the current file is uploaded (if uploading multiple files)
2. saving the count of current transfered bytes and sending the resume command to the ftp server by giving the count as argument. But not all FTP server are set up to support file resume. so guess option 1 wit will be.

Problem solved.

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