[C#/UWP] SuspendingDeferral 클래스 : 비동기 처리 대기하기

using Windows.ApplicationModel;
using Windows.Storage;
using Windows.UI.Xaml;
using Windows.UI.Xaml.Controls;

...

private TextBox textBox;

...

Application.Current.Suspending += Application_Suspending;

...

private async void Application_Suspending(object sender, SuspendingEventArgs e)
{
    SuspendingDeferral suspendingDeferral = e.SuspendingOperation.GetDeferral();

    await PathIO.WriteTextAsync("ms-appdata:///local/sample.txt", this.textBox.Text);

    suspendingDeferral.Complete();
}