DoEvents for WPF

private static DispatcherOperationCallback exitFrameCallback = new DispatcherOperationCallback(ExitFrame);

        public static void DoEvents() {
            // Create new nested message pump.
            DispatcherFrame nestedFrame = new DispatcherFrame();

            // Dispatch a callback to the current message queue, when getting called,
            // this callback will end the nested message loop.
            // note that the priority of this callback should be lower than the that of UI event messages.
            DispatcherOperation exitOperation = Dispatcher.CurrentDispatcher.BeginInvoke(
                DispatcherPriority.Background,exitFrameCallback,nestedFrame);

            // pump the nested message loop, the nested message loop will
            // immediately process the messages left inside the message queue.
            Dispatcher.PushFrame(nestedFrame);

            // If the "exitFrame" callback doesn't get finished, Abort it.
            if(exitOperation.Status != DispatcherOperationStatus.Completed) {
                exitOperation.Abort();
            }
        }

        // Exit the nested message loop.
        private static Object ExitFrame(Object state) {
            DispatcherFrame frame = state as DispatcherFrame;
            frame.Continue = false;
            return null;
        }