有没有办法取消StorageFile.CopyAsync（）？

Question

In Win8, I use somefile.CopyAsync(destFolder, newName) to copy files. But when I try to cancel it, it appears doesn't work. These two method are how I try to cancel it:

1. just use IAsyncOperation.Cancel

    var op = somefile.CopyAsync(destFoder, newName); op.Cancel(); op.Complete = (x,y) => { switch(y) { case AsyncStatus.Complete: Debug.WriteLine("Completed" + x.GetResults().Name); break; case AsyncStatus.Cancel: Debug.WriteLine("Canceled") break; } } 

2. use AsTask(CancellationToken)

    var cts = new CancellationTokenSource(); cts.CancelAfter(TimeSpan.FromSeconds(1)); var op = somefile.CopyAsync(destFolder, newName).AsTask(cts.Token); await op; 

In first method, case AsyncStatus.Cancel doesnt be called, and in second method, nothing happens too.Is there any other way I can try? Thanks!

Answer 1

Have you tried this...

var task = file.CopyAsync(KnownFolders.DocumentsLibrary, "test").AsTask();
task.AsAsyncAction().Cancel();

It worked in my simple test.

This code should work as well if you want to use cancellation tokens

var source = new CancellationTokenSource(TimeSpan.FromMilliseconds(500));
var token = source.Token;
token.Register(() => { Debug.WriteLine("Your cancellation code here"); });
var task = file.CopyAsync(KnownFolders.DocumentsLibrary, "test").AsTask(token);