取消任务

Question

I need to cancel task that using a long-running method from dll (MethodFromDll() in this example) Where I can call cancellationToken.ThrowIfCancellationRequested() method to cancel this Task?

tokenSource = new CancellationTokenSource();
CancellationToken cancellationToken = tokenSource.Token;        

t = Task.Factory.StartNew(() => {
try {
    ...some code
    // I need to cancel this task manually if method not answer
    // or there is no wish to wait
    MethodFromDll(); 
   ...some code
    } catch {
         ...some code
    }
}, cancellationToken);

Answer 1

Call Cancel on your CancelationTokenSource and register callback

tokenSource = new CancellationTokenSource();
CancellationToken cancellationToken = tokenSource.Token;

return Task.Factory.StartNew(() =>
{
    try
    {
        cancellationToken.Register(() =>
        {
            //call api method to stop long running method 
        });
        //...some code
    }
    catch
    {

    }
}, cancellationToken);