How to start BackgroundWorker after CancelAsync

I'm using backgroundworker in UserControls which I'm loading into panels by a button click. I hit CancelAsync BW in one UC, then I go to another UC. When I want to return to previous UС (where I've canceled BW) I always enter RunWorkerCompleted event.

I've tried to re-initialize BW in UC constructor:

bgrWorker = new BackgroundWorker
        {
            WorkerSupportsCancellation = true,
            WorkerReportsProgress = true
        };

        bgrWorker.DoWork += DoWork;
        bgrWorker.ProgressChanged += ProgressChanged;
        bgrWorker.RunWorkerCompleted += RunWorkerCompleted;

        btnStop.Click += StopWorker;

But it doesn't work.

Code of DoWork event:

System.Threading.Tasks.Parallel.For(0, _list.Count, num =>
            {
  开发者_JS百科              if (bgrWorker.CancellationPending)
                {
                    e.Cancel = true;
                }
                else
                {
                    _splittedList.Add(FindMiddle.Find(_list[num], 20));
                    bgrWorker.ReportProgress(0);
                }
            });

(As instructed in comments :)

When you return to the previous user control, that won't rerun the constructor - so if you need to reinitialize the BackgroundWorker at that point, you need to move the initialization code into a method that can be run at the appropriate time.