首先，我们设计好一个Blank App程序，在添加Button和BlockText控件，在Button中找出Click事件，再单击进入事件。其中xaml中代码显示为：

      其次，用FolderPicker类new一个实例folderPicker ，在调用属性 SuggestedStartLocation设定起始位置。接着用FileTypeFilter.Add增加可以识别的文件类型。再用StorageFolder类新建一个实例，等待异步PickSingleFolderAsync方法， 获得一个目录。 通过StorageApplicationPermissions.FutureAccessList.AddOrReplace方法，得到选择的目录权限。最后，将它的目录名显示到BlockText中。按F5演示成功。其中事件中代码如下：

private async void Folder_Click(object sender, RoutedEventArgs e)        {            FolderPicker folderPicker = new FolderPicker();            folderPicker.SuggestedStartLocation = PickerLocationId.Desktop;            folderPicker.FileTypeFilter.Add(".docx");            folderPicker.FileTypeFilter.Add(".xlsx");            folderPicker.FileTypeFilter.Add(".pptx");            StorageFolder folder = await folderPicker.PickSingleFolderAsync();            if (folderPicker != null)            {                StorageApplicationPermissions.FutureAccessList.AddOrReplace("PickedFolderToken", folder);                Foutput.Text = "Picked folder: " + folder.Name;            }            else            {                Foutput.Text = "Operation cancelled.";            }        }