private void Image_MouseLeftButtonDown_1(object sender, MouseButtonEventArgs e)
        {
            ProductDocViewViewModel productDocViewViewModel = this.DataContext as ProductDocViewViewModel;

            productDocViewViewModel.HideExpander();
        }
        // 当用户导航到此页面时执行。
        protected override void OnNavigatedTo(NavigationEventArgs e)
        {
            ProductDocViewViewModel productDocViewViewModel = this.DataContext as ProductDocViewViewModel;

            productDocViewViewModel.LoadData();
        }