如何取消HostingEnvironment.QueueBackgroundWorkItem

本文介绍了如何取消HostingEnvironment.QueueBackgroundWorkItem的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述

是否可以取消使用 HostingEnvironment.QueueBackgroundWorkItem 进行的后台任务？

Is there a way to cancel background task made with HostingEnvironment.QueueBackgroundWorkItem?

有 CancellationToken 通知任务是否被取消，但是我该怎么办？ 引用 https：// msdn。 microsoft/en-us/library/dd997396(v=vs.110).aspx

There is CancellationToken which notifies if tasks was cancelled but how can i do it? Refering to msdn.microsoft/en-us/library/dd997396(v=vs.110).aspx

成功取消涉及请求代码调用CancellationTokenSource.Cancel方法

A successful cancellation involves the requesting code calling the CancellationTokenSource.Cancel method

确定。经过几次试验后，我在哪里可以访问 CancellationTokenSource ？

OK. Where can i get access to CancellationTokenSource?

推荐答案

提出了解决方案：

HostingEnvironment.QueueBackgroundWorkItem(ct => { var linkedTokenSource = CancellationTokenSource.CreateLinkedTokenSource(ct); var cancellationToken = linkedTokenSource.Token; return Task.Factory.StartNew(() => { // do stuff on background }, cancellationToken); });

更新：

实际上，不需要任务。感谢svick提出来。 这是没有任务的更详细的代码示例。

Indeed, task is not needed. Thanks svick for bringing that up. Here is a bit more detailed code sample without task.

HostingEnvironment.QueueBackgroundWorkItem(ct => { var linkedTokenSource = CancellationTokenSource.CreateLinkedTokenSource(ct); // following is a dummy method, but you get the idea. // StoreCancellationTokenSourceSoItCanBeUsedSomewhereElse(linkedTokenSource); var cancellationToken = linkedTokenSource.Token; try { while(true) { cancellationToken.ThrowIfCancellationRequested(); // do bg stuff } } catch (OperationCanceledException ex) { // either token is in cancelled state } });