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    <p>I know that this question is ancient, but hell - I found it, and I figure that others might as well. I'm trying to resolve a related issue, and might have some insight. </p> <p>You mentioned Dustin Campbell's WeakEventHandler - it indeed cannot work with anonymous methods by design. I was trying to fiddle something together that would, when I realized that a) in 99% of cases I'd need something like this his original solution would be safer, and b) in those few cases where I have to (note: have to, not "want to because lambdas are so much prettier and concise") it's possible to make it work if you get a little clever. </p> <p>Your example seems like exactly the kind of one-off case where getting a little tricky can result in a fairly concise solution.</p> <pre><code> public static class Linker { public static void Link(Publisher publisher, Control subscriber) { // anonymous method references the subscriber only through weak // references,so its existance doesn't interfere with garbage collection var subscriber_weak_ref = new WeakReference(subscriber); // this instance variable will stay in memory as long as the anonymous // method holds a reference to it we declare and initialize it to // reserve the memory (also, compiler complains about uninitialized // variable otherwise) EventHandler&lt;ValueEventArgs&lt;bool>> handler = null; // when the handler is created it will grab references to the local // variables used within, keeping them in memory after the function // scope ends handler = delegate(object sender, ValueEventArgs&lt;bool> e) { var subscriber_strong_ref = subscriber_weak_ref.Target as Control; if (subscriber_strong_ref != null) subscriber_strong_ref.Enabled = e.Value; else { // unsubscribing the delegate from within itself is risky, but // because only one instance exists and nobody else has a // reference to it we can do this ((Publisher)sender).EnabledChanged -= handler; // by assigning the original instance variable pointer to null // we make sure that nothing else references the anonymous // method and it can be collected. After this, the weak // reference and the handler pointer itselfwill be eligible for // collection as well. handler = null; } }; publisher.EnabledChanged += handler; } } </code></pre> <p>The WPF Weak Event pattern is rumored to come with a lot of overhead, so in this particular situation I wouldn't use it. Furthermore, referencing the core WPF library in a WinForm app seems a little heavy as well.</p>
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    1. COThe question may be ancient, but it still interests me! I've added your solution to my test application and it appears to work, so it is my privilege to award you your first green tick!
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    2. COThanks! You might also check out my version of Dustin Campbell's implementation. I posted it as an answer to this question: http://stackoverflow.com/questions/1089309/weak-events-in-net/1483010#1483010
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    3. COOuf! That one's a bit complicated for me, I'll have to take time to disect it. I've got another version of this one brewing...
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