The correct way to Fire-and-Forget an asynchronous delegate
Consider me rusty on the subject of asynchronous delegates.
If I want to call a method asynchronously, in a fire-and-forget style, is this an appropriate way to do it?
Action action = DoSomething;
action.BeginInvoke(action.EndInvoke, null);
The DoSomething()
method catches all exceptions and deals with them internally.
Is the call to EndInvoke
appropriate? Required?
Is the开发者_高级运维re a clearer way to achieve the same behaviour?
The new way (in .NET 4) is to do this:
Task.Factory.StartNew(() => DoSomething());
The "old-school" way in .NET 3.5 is to use the ThreadPool
:
ThreadPool.QueueUserWorkItem(s => DoSomething());
If you prefer to use asynchronous delegates, then you should know that the call to EndInvoke
is necessary, even if you don't have any additional code you wish to execute on callback.
It should be noted that
Task.Factory.StartNew(() => DoSomething());
fails to observe any potential exception thrown by the DoSomething method. I know this is what one wants when starting a fire-and-forget operation, but as far as .Net 4 is concerned, any task with an unobserved exception being finalized by the garbage collector would escalate as an unhandled exception that will kill your process. However, in .Net 4.5, the default behavior has changed (see the async & await keywords).
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