Question

This is the dowork code. I have even stepped through this. After e.cancel = true, DoWork runs once more ,it gets to the while loop, it sets e.Cancel to true again and then exits the function and never runs the Completed function.

private void backgroundWorker2_DoWork(object sender, DoWorkEventArgs e)
    {
        BackgroundWorker worker = sender as BackgroundWorker;
        //While the song is not over
          while (!worker.CancellationPending )
          {

              if (progressBar1.Value == progressBar1.Maximum)
              {

                  e.Cancel = true;
                  return;
              }
              else
              {
                  //Keep ticking the progress bar one second
                  worker.ReportProgress(0);
                  Thread.Sleep(1000);
              }
          }
          e.Cancel = true;
          return;



    }

Here is the code that cancels the worker. the WaitOne() will block untill it gets a signal from the RunWorkerCompleted.

if (this.backgroundWorker2.IsBusy)
        {
            this.backgroundWorker2.CancelAsync();

            _resetEvent.WaitOne();

        }

EDIT: Note that I have done this VV

backgroundWorker2.RunWorkerCompleted += backgroundWorker2_RunWorkerCompleted;
backgroundWorker2.WorkerSupportsCancellation = true;

Answer 1

did you set

BackgroundWorker.WorkerSupportsCancellation = true

?