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PO.NET: How to have background thread signal main thread data is available?
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copied!<p>What is the proper technique to have <strong>ThreadA</strong> signal <strong>ThreadB</strong> of some event, without having <strong>ThreadB</strong> sit blocked waiting for an event to happen?</p> <p>i have a background thread that will be filling a shared List<T>. i'm trying to find a way to asynchronously signal the "main" thread that there is data available to be picked up.</p> <hr> <p>i considered setting an event with an EventWaitHandle object, but i can't have my main thread sitting at an Event.WaitOne().</p> <hr> <p>i considered having a delegate callback, but a) i don't want the main thread doing work in the delegate: the thread needs to get back to work adding more stuff - i don't want it waiting while the delegate executes, and b) the delegate needs to be marshalled onto the main thread, but i'm not running a UI, i have no Control to .Invoke the delegate against.</p> <hr> <p>i considered have a delegate callback that simply starts a zero interval System.Windows.Forms.Timer (with thread access to the timer synchronized). This way the thread only needs to be stuck as it calls</p> <p><code>Timer.Enabled = true;</code></p> <p>but that seems like a hack.</p> <p>In the olden days my object would have created a hidden window and had the thread post messages to that hidden windows' HWND. i considered creating a hidden control, but i gather that you cannot .Invoke on a control with no handle created. Plus, i have no UI: my object could have been created on a web-server, service, or console, i don't want there to be a graphical control appearing - nor do i want to compile a dependency on System.Windows.Forms.</p> <hr> <p>i considered having my object expose an ISynchronizeInvoke interface, but then i would need to implement .Invoke(), and that's my problem.</p> <hr> <p>What is the proper technique to have thread A signal thread B of some event, without having thread B sit blocked waiting for an event to happen?</p>

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