ThreadPool.QueueUserWorkItem and EndInvoke

Question

Do I need to call the EndInvoke on a delegate passed to ThreadPool.QueueUserWorkItem?

I am using this suggestion to call the ThreadPoolQueueWorkItem.

ThreadPool.QueueUserWorkItem(
    delegate { someDelegate(arg1, arg2); }
);

If i need to call endinvoke, how do I call it? Thanks.

Answer 1

No, you don't need to call it. In fact, you shouldn't :-)

You should only call EndInvoke to end an asynchronous invocation previously started by calling BeginInvoke.

In the code you have provided you are running the delegate synchronously from a ThreadPool thread.

This approach is just fine when you have a "fire and forget" requirement. However, if you need to retrieve output from the invocation it would be better to use BeginInvoke followed by EndInvoke.

Answer 2

You don't need to, no, but according to MSDN you should to avoid potential memory leaks. Here's a great blog post by Phil Haack discussing the issue, as well as his helper class for fire and forget use cases.