Transcript public Task FooAsync() { var tcs = new TaskCompletionSource (); public async Task Task Delay(int Task RunAsync(Func RunStoryboardAsync(this WaitForClickAsync(this milliseconds) func) Button Storyboard button) sb) { var tcs = new TaskCompletionSource (); TaskCompletionSource (); // schedule something asynchronously // to invoke tcs.Set* RoutedEventHandler EventHandler ThreadPool.QueueUserWorkItem(delegate new Timer(_ => tcs.SetResult(true)).Change(milliseconds, handler handler =