public static class WindowEx

{

public static void DoEvents(this Window obj)

{

DispatcherFrame frame = new DispatcherFrame();

Dispatcher.CurrentDispatcher.BeginInvoke(DispatcherPriority.Background,

new DispatcherOperationCallback(delegate (object f)

{

((DispatcherFrame)f).Continue = false;

                return null;
            }
                ), frame);
        Dispatcher.PushFrame(frame);
    }
}