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How can I abort/cancel the forwarded BackgroundWorker?

As you can see here there is a backgroundworker for the ftp-transfer.
Franks answer shows a new class with some overrided methods, so that it is possible to get the transfer speed and the percentage of it.

I want to cancel the backgroundworker which runs the upload, but I dont know how.

Implementation

public UpAndDownloadForm(Job pJob)
    {
        InitializeComponent();
        this.job = pJob;
        bGroundWorker = new BackgroundWorker();
        bGroundWorker.WorkerReportsProgress = true;
        bGroundWorker.WorkerSupportsCancellation = true;

        bGroundWorker.DoWork += new DoWorkEventHandler(bGroundWorker_DoWork);
        bGroundWorker.ProgressChanged += new ProgressChangedEventHandler(bGroundWorker_ProgressChanged);
        bGroundWorker.RunWorkerCompleted += new RunWorkerCompletedEventHandler(bGroundWorker_RunWorkerCompleted);

        bGroundWorker.RunWorkerAsync(pJob);
    }

DoWork:

void bGroundWorker_DoWork(object sender, DoWorkEventArgs e)
    {
        streamWithTransferSpeedWorker = (BackgroundWorker)sender;
        Job job = (Job)e.Argument;
        string[] files = Directory.GetFiles(job.GetSourceFolder(), "*.*", SearchOption.AllDirectories);

        if (bGroundWorker.CancellationPending) //Falls der bGWorker abgebrochen wurde, beendet man diesen wohl einfach mit e.Cancel;
        {
            e.Cancel = true;
            return;
        }
        foreach (string file in files)
        {
            char[] temp = file.ToCharArray(); //Dateipfad in CharArray speichern
            Array.Reverse(temp); //Reihenfolge ändern (von hinten nach vorne)
            string fileReversed = new string(temp); //als string speichern
            int index = fileReversed.IndexOf(@"\"); //die Zeichenlänge des DateiNAMENs auslesen
            string fileOnlyName = file.Substring(file.Length - index, index); //nur den Dateinamen auslesen


            FtpWebRequest request = (FtpWebRequest)WebRequest.Create(job.GetDestinationFolder() + "\\" + fileOnlyName);
            request.Method = WebRequestMethods.Ftp.UploadFile;
            request.Credentials = new NetworkCredential(Manager._user, Manager._password);


            var response = (FtpWebResponse)request.GetResponse(); //WebResponse response = request.GetResponse(); 

            using (Stream source = File.OpenRead(file))
            {
                using (var destination = new StreamWithTransferSpeed(request.GetRequestStream(), streamWithTransferSpeedWorker, source.Length))//request.ContentLength))
                {
                    source.CopyTo(destination);
                }
            }

            Console.WriteLine("Upload File Complete, status {0}", response.StatusDescription);
            response.Close();
        }
    }

Cancel BackgroundWorker:

private void btnCancelLoad_Click(object sender, EventArgs e)
    {
        if (bGroundWorker.IsBusy)
        {
            bGroundWorker.CancelAsync();
        }
        if (streamWithTransferSpeedWorker.IsBusy)
        {
            streamWithTransferSpeedWorker.CancelAsync();
        }
    }


As you can see I already tried something, but it dont make any sense.
The Backgroundworker- CancellationPending -Flag for starting the upload is true after Button-Click-Event, but the Upload is still running.

Do I missunderstand something ?
During writing this question, I thought about canceling the CopyTo -Method, but I even dont know whether this works or whether this is the problem/solution.
Thanks for help.


EDIT1:
Here you can see the forwarded BackgroundWorker using (var destination = new StreamWithTransferSpeed(request.GetRequestStream(), streamWithTransferSpeedWorker, source.Length)) .


EDIT2:
As T MCKeown said: instance of bool
UploadForm.cs:

 private void btnCancelLoad_Click(object sender, EventArgs e) { if (bGroundWorker.IsBusy) { bGroundWorker.CancelAsync(); Manager._cancelBackgroundWorker = true; } } 

and additionally my part:
StreamWithTransferSpeed.cs:

 if (Manager._cancelBackgroundWorker) { this.worker.CancelAsync(); //this is useless, because the Backgroundworker is still running Manager._cancelBackgroundWorker = false; innerStream.Close(); //this is dirty, but it works, after the Closing the backgroundworker is canceled } 

and here you can see the CancelAsync() . It's executed at Console.WriteLine("bGW direkt unter der exception abgebrochen"); :
UploadForm.cs:

 void bGroundWorker_DoWork(object sender, DoWorkEventArgs e) { BackgroundWorker worker = (BackgroundWorker)sender; Job job = (Job)e.Argument; string[] files = Directory.GetFiles(job.GetSourceFolder(), "*.*", SearchOption.AllDirectories); foreach (string file in files) { if (bGroundWorker.CancellationPending) //Falls der bGWorker abgebrochen wurde, beendet man diesen wohl einfach mit e.Cancel; { e.Cancel = true; //Sinnlos da es eh nicht funktioniert Console.WriteLine("bGW direkt unter foreach abgebrochen"); return; } char[] temp = file.ToCharArray(); //Dateipfad in CharArray speichern Array.Reverse(temp); //Reihenfolge ändern (von hinten nach vorne) string fileReversed = new string(temp); //als string speichern int index = fileReversed.IndexOf(@"\\"); //die Zeichenlänge des DateiNAMENs auslesen string fileOnlyName = file.Substring(file.Length - index, index); //nur den Dateinamen auslesen FtpWebRequest request = (FtpWebRequest)WebRequest.Create(job.GetDestinationFolder() + "\\\\" + fileOnlyName); request.Method = WebRequestMethods.Ftp.UploadFile; request.Credentials = new NetworkCredential(Manager._user, Manager._password); var response = (FtpWebResponse)request.GetResponse(); //WebResponse response = request.GetResponse(); try { using (Stream source = File.OpenRead(file)) { using (var destination = new StreamWithTransferSpeed(request.GetRequestStream(), worker, source.Length))//request.ContentLength)) { source.CopyTo(destination); } } } catch (Exception ex) { if (ex.GetType() == typeof(ObjectDisposedException)) { Console.WriteLine("Upload canceled."); if (bGroundWorker.CancellationPending) //Falls der bGWorker abgebrochen wurde, beendet man diesen wohl einfach mit e.Cancel; { e.Cancel = true; //Sinnlos da es eh nicht funktioniert Console.WriteLine("bGW direkt unter der exception abgebrochen"); return; } } } Console.WriteLine("Upload File Complete, status {0}", response.StatusDescription); response.Close(); } } 

Create an instance _cancel variable of type bool

private void btnCancelLoad_Click(object sender, EventArgs e)
{
  _cancel = true;
  ...
}

Then check it here:

foreach (string file in files)
    {
       if (_cancel ) return;

        char[] temp = file.ToCharArray(); //Dateipfad in CharArray speichern
        ...

Add the if statement any where else you may want to check for cancel.

RESPONSE to EDIT2:

You changed your code to this:

foreach (string file in files)
    {
        if (bGroundWorker.CancellationPending) //Falls der bGWorker abgebrochen wurde, beendet man diesen wohl einfach mit e.Cancel;
        {
            e.Cancel = true; //Sinnlos da es eh nicht funktioniert
            Console.WriteLine("bGW direkt unter foreach abgebrochen");
            return;
        }

I had suggested you do something like this:

foreach (string file in files)
    {
        if (Manager._cancelBackgroundWorker) //Falls der bGWorker abgebrochen wurde, beendet man diesen wohl einfach mit e.Cancel;
        {
            e.Cancel = true; //Sinnlos da es eh nicht funktioniert
            Console.WriteLine("bGW direkt unter foreach abgebrochen");
            return;
        }

You set this boolean to true upon clicking cancel yes?

Put Cancel check code in Foreach loop

if (bGroundWorker.CancellationPending) //Falls der bGWorker abgebrochen wurde, beendet man diesen wohl einfach mit e.Cancel;
{
    e.Cancel = true;
    return;
}

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