c# - storagefile.OpenStreamForReadAsync 返回错误

Question

当我尝试返回流时，通用 Windows 平台 10 TargetFile.OpenStreamForReadAsync() 给我一个错误“附加信息：访问被拒绝。（来自 HRESULT 的异常：0x80070005（E_ACCESSDENIED））”

public static async void StartReadFile(StorageFile TargetFile)
    {


        var stream = await TargetFile.OpenStreamForReadAsync();

        ZipArchive z = new ZipArchive(stream);
        var worksheet = z.GetEntry("xl/worksheets/sheet1.xml");
        var sharedString = z.GetEntry("xl/sharedStrings.xml");
    }

 private async  void PickUpFileButton_Click(object sender, RoutedEventArgs e)
    {
        string content = null;
        FileOpenPicker openPicker = new FileOpenPicker();
        openPicker.SuggestedStartLocation = PickerLocationId.Desktop;
        openPicker.FileTypeFilter.Add(".xlsx");
        StorageFile file = await openPicker.PickSingleFileAsync();
        ExcelFileReader.StartReadFile(file);
        if(file != null)
        {
            content = "file is saved";
        }
        else
        {
            content = "no file is saved";
        }
    }