cancellation-token

问题 When I cancel my async method with the following content by calling the Cancel() method of my CancellationTokenSource , it will stop eventually. However since the line Console.WriteLine(await reader.ReadLineAsync()); takes quite a bit to complete, I tried to pass my CancellationToken to ReadLineAsync() as well (expecting it to return an empty string) in order to make the method more responsive to my Cancel() call. However I could not pass a CancellationToken to ReadLineAsync() . Can I cancel

问题 Is there a way to cancel background task made with HostingEnvironment.QueueBackgroundWorkItem ? There is CancellationToken which notifies if tasks was cancelled but how can i do it? Refering to https://msdn.microsoft.com/en-us/library/dd997396(v=vs.110).aspx A successful cancellation involves the requesting code calling the CancellationTokenSource.Cancel method OK. Where can i get access to CancellationTokenSource ? 回答1: After few trials i came up with the soulution: HostingEnvironment

问题 This question already has answers here : Closed 7 years ago . Possible Duplicate: Cancellation token in Task constructor: why? This method receives a CancellationToken: CancellationTokenSource cts = new CancellationTokenSource(4); var t = Task.Factory.StartNew(() => { // code }, cts.Token); Since cancellation is cooperative (the actual working code needs to observe the cancellation token), What is the purpose of passing this to the StartNew method as an argument? 回答1: It allows the task

问题 I have a Task which is always blocked and I have a CancellationToken passed into it which is used to cancel the task. However the Continuation task is never executed which is set to execute on Task's cancellation. The code is: _tokenSrc = new CancellationTokenSource(); var cnlToken = _tokenSrc.Token; Task.Run(() => // _stream.StartStream() blocks forever _stream.StartStream(), cnlToken) .ContinueWith(ant => { _logger.Warn("Stream task cancellation requested, stopping the stream"); _stream

问题 There are many reasons to put a token in the constructor of a task, mentioned here: Cancellation token in Task constructor: why? With the use of keywords, async / await, how is that working? for example my code below: public async Task MethodAsync(CancellationToken token) { await Method01Async(); await Method02Async(); } Although it is an asynchronous process. In no time I used "Task.StartNext" or "Task.Run" or "new Task". To be able to specify my cancellation token, how can I do? 回答1: You

问题 There are many reasons to put a token in the constructor of a task, mentioned here: Cancellation token in Task constructor: why? With the use of keywords, async / await, how is that working? for example my code below: public async Task MethodAsync(CancellationToken token) { await Method01Async(); await Method02Async(); } Although it is an asynchronous process. In no time I used "Task.StartNext" or "Task.Run" or "new Task". To be able to specify my cancellation token, how can I do? 回答1: You

问题 There are different examples for async controllers. Some of them use CancellationToken in method definition: public async Task<ActionResult> ShowItem(int id, CancellationToken cancellationToken) { await Database.GetItem(id, cancellationToken); ... But other examples and even the default ASP.NET projects for VS2013 don't use CancellationToken at all and work without it: public async Task<ActionResult> ShowItem(int id) { await Database.GetItem(id); ... It's not clear, if we should use

问题 http://msdn.microsoft.com/en-us/library/dd988458.aspx UPD : so, let's discuss this article then: http://msdn.microsoft.com/en-us/library/dd997396.aspx I've changed that code a little: static void Main() { var tokenSource2 = new CancellationTokenSource(); CancellationToken ct = tokenSource2.Token; var task = Task.Factory.StartNew(() => { // Were we already canceled? ct.ThrowIfCancellationRequested(); bool moreToDo = true; Thread.Sleep(5000); while (moreToDo) { // Poll on this property if you

问题 I want to cancel a running task (when the users presses the escape key). when i click on "escape" key Form_KeyDown run but doesn't cancel task! CancellationTokenSource tokenSource = new CancellationTokenSource(); CancellationToken token=new CancellationToken(); private async void Search_Button_ClickAsync(object sender, EventArgs e) { token = tokenSource.Token; await (Task.Factory.StartNew(() => { //...my program }, token)); private void Form_KeyDown(object sender, KeyEventArgs e) { if (e

问题 I have been playing round with the async ctp this morning and have a simple program with a button and a label . Click the button and it starts updating the label , stop the button it stops writing to the label . However, I'm not sure how to reset the CancellationTokenSource so that I can restart the process. My code is below: public partial class MainWindow : Window { CancellationTokenSource cts = new CancellationTokenSource(); public MainWindow() { InitializeComponent(); button.Content =