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    <p>I know this is an old post, but just in case anyone comes across it, it is certainly possible to do this. You declare your own delegate that returns a value, then base the event off this new delegate. Here is an example:</p> <p>In the event declarer / publisher:</p> <pre><code>// the delegate public delegate string ReturnStringEventHandler(object sender, EventArgs args); // the event public event ReturnStringEventHandler StringReturnEvent; // raise the event protected void OnStringReturnEvent(EventArgs e) { if (StringReturnEvent != null) // make sure at least one subscriber // note the event is returning a string string myString = StringReturnEvent(this, e); } </code></pre> <p>In the event subscriber:</p> <pre><code>// Subscribe to event, probably in class constructor / initializer method StringReturnEvent += HandleStringReturnEvent; // Handle event, return data private string HandleStringReturnEvent(object sender, EventArgs e) { return "a string to return"; } </code></pre> <p>.NET provides an example of this in the AssemblyResolve event, which uses the ResolveEventHandler delegate to return data, in this case a reference to the desired Assembly. <a href="http://msdn.microsoft.com/en-us/library/system.appdomain.assemblyresolve.aspx" rel="noreferrer">MSDN Article on AssemblyResolve event</a></p> <p>I have personally used both the AssemblyResolve event and the custom delegate technique to return data from an event, and they both work as expected on Visual Studio 2010.</p>
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    1. POPass a return value back through an EventHandler
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    1. COIf you use the custom delegate approach, what happens if you have multiple handlers of the event returning different values? Which return value is received by the event raiser?
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    2. COYou mentioned a definite draw-back to this approach. The last event handler to be registered with the event is the one whose value will be returned. http://msdn.microsoft.com/en-us/library/aa691375%28VS.71%29.aspx In the "AssemblyResolve" event I mentioned, this is OK, since its only intended to be used one at a time, but you're right - in general, this would be a poor design choice if multiple return values are required.
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