WPF: Mouse left button click and hold down handling

Question

How do I repetitively perform an action when the mouse left button is pressed and held down in WPF?

The following event handler for the UIElement.PreviewMouseLeftButtonDown event does not get the job done:

private void BaseButtonRight_MouseLeftButtonDown(object sender, System.Windows.Input.MouseButtonEventArgs e)
        {
           // keep performing action while mouse left button is pressed.  
           // Checking e.ButtonState works only for one click

        }

Execution does not even get into the while loop and handler is called when the left mouse button is released!

Answer 1

Why not use a RepeatButton?

http://msdn.microsoft.com/en-us/library/ms746649(v=vs.85).aspx

Answer 2

Start a BackroundWorker which exits when the mouse has been released. Set a flag with the mouse up event and also check periodically in the BackgroundWorker DoWork function. Make sure you use lock { } around accessing the flag.

Edit: in case you want to access something on the UI thread, use Dispatcher.BeginInvoke, for example:

Dispatcher.BeginInvoke(new ThreadStart(delegate
{
    ComboBoxItem selItem = ComboboxConnectString.SelectedItem as ComboBoxItem;
    if (selItem != null && selItem.Tag is string)
        ComboboxConnectString.Text = (string)selItem.Tag;
}));