Execute task in background in WPF application

Question

Example

private void Start(object sender, RoutedEventArgs e)
{
    int progress = 0;
    for (;;)
    {
        System.Threading.Thread.Sleep(1);
        progress++;
        Logger.Info(progress);
    }
}

What is the recommended approach (TAP or TPL or BackgroundWorker or Dispatcher or others) if I want Start() to

1. not block the UI thread
2. provide progress reporting
3. be cancelable
4. support multithreading

Answer 1

With .NET 4.5 (or .NET 4.0 + Microsoft.Bcl.Async), the best way is to use Task-based API and async/await. It allows to use the convenient (pseudo-)sequential code workflow and have structured exception handling.

Example:

private async void Start(object sender, RoutedEventArgs e)
{
    try
    {
        await Task.Run(() =>
        {
            int progress = 0;
            for (; ; )
            {
                System.Threading.Thread.Sleep(1);
                progress++;
                Logger.Info(progress);
            }
        });
    }
    catch (Exception ex)
    {
        MessageBox.Show(ex.Message);
    }
}

More reading:

How to execute task in the WPF background while able to provide report and allow cancellation?

Async in 4.5: Enabling Progress and Cancellation in Async APIs.

Async and Await.

Async/Await FAQ.