[Window Store app]DownloadOperation,回调操作状态异常? 表象解决方案

创建下载 :

download = downloader.CreateDownload(source, destinationFile);

Progress<DownloadOperation> progressCallback = new Progress<DownloadOperation>(DownloadProgress);

cts = new CancellationTokenSource();
download.StartAsync().AsTask(cts.Token, progressCallback);

　　

正常回调:

private void DownloadProgress(DownloadOperation download)
{
    if (download.Progress.Status == BackgroundTransferStatus.Completed)
    {
        //operation
    }
}
　　

download.Progress.Status ==    BackgroundTransferStatus.Completed 打断点 都是可以进入, 不打断电,下载后的操作就有异常,未找到原因,所以,偷鸡搞面延迟操作,解决了,不知道哪位能解释下问题何在?

ok 代码:

private void DownloadProgress(DownloadOperation download)
{

　　ThreadPoolTimer.CreateTimer(async (timer) =>
　　{
    　if (download.Progress.Status ==    BackgroundTransferStatus.Completed)
　　　{
    　　await Dispatcher.RunAsync(CoreDispatcherPriority.Normal, () =>
    　　{
        //operation
    　　});
    　}
　　}, TimeSpan.FromSeconds(1));
}