How to ensure background thread ends when application ends?

I have an asp.net application with a background thread. The thread starts when the application starts and it is gracefully stopped when the application ends. I am running the webs开发者_高级运维ite on a shared host. Unfortunately sometimes the application does not trigger the Application_End event when it ends. I would think that the threads would be killed anyway, but that's not the case. I currently have 4 threads running in the background. Three from previous times the application started and 1 from the current application session. How can I ensure that the threads are shutdown when the application ends? Is there a way for the threads to check if the application was reset or had been reset? Or is there a way to check for these rogue threads at application startup and kill them? Thanks in advance.

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Use the ThreadPool.QueueUserWorkItem() to execute your code in the background, which will be ended when the AppDomain unloads. I'm assuming that you are using a backgroundworker, according to the tags, and I would suggest trying this instead. (Consider adding sample code to draw out better answers.)

Managed ThreadPool: http://msdn.microsoft.com/en-us/library/0ka9477y.aspx

Foreground/Background Threads: http://msdn.microsoft.com/en-us/library/h339syd0.aspx