Weak events in .NET?

.net events garbage-collection weak-references
tom7 picture tom7 · Jul 6, 2009 · Viewed 7.4k times · Source

If object A listens to an event from object B, object B will keep object A alive. Is there a standard implementation of weak events that would prevent this? I know WPF has some mechanism but I am looking for something not tied to WPF. I am guessing the solution should use weak references somewhere.

Answer

Judah Gabriel Himango picture Judah Gabriel Himango · Jul 6, 2009

Dustin Campbell from the DidItWith.NET blog examines several of the failed attempts to create weak event handlers, then goes on to show a valid, working, lightweight implementation: Solving the Problem With Weak Event Handlers.

Ideally, though, Microsoft would introduce the concept into the language itself. Something like:

Foo.Clicked += new weak EventHandler(...);

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