private async void btnEcho_Click(object sender, RoutedEventArgs e) { var window = new Windows.Echo { Owner = this }; if (window.ShowDialog() ?? false) { try { WriteLine("Method: Echo"); WriteLine("Request: {0}", window.Value); var result = await Client.EchoAsync(new EchoData { Message = window.Value }); WriteLine("Response: {0}", result.Message); } catch (System.Exception ex) { WriteLine("Error: {0}", ex.Message); } } }