private async void btnCleanup_Click(object sender, RoutedEventArgs e)
{
await FileListHelper.Cleanup();
// Enumerate the files and folders in the local folder.
await ListFilesInLocalFolderAsync();
}
// Code to execute when the application is closing (eg, user hit Back)
// This code will not execute when the application is deactivated
private async void Application_Closing(object sender, ClosingEventArgs e)
{
await FileListHelper.Cleanup();
}