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In C#, events are typically implemented using delegates. When an object subscribes to an event, it creates a delegate that references the event handler method in the object that will be notified when the event occurs.

In terms of reference counting, when an object subscribes to an event, the event delegate keeps a reference to the object. As long as the event delegate is alive, the object will not be garbage collected. However, when the object is no longer needed and is eligible for garbage collection, it needs to be unsubscribed from the event to prevent memory leaks.

In order to address this issue, C# provides the WeakEventManager class that allows subscribers to register for events using weak references, which are not counted by the garbage collection. This allows the garbage collector to collect the subscriber, even if it is still subscribed to the event, and it frees the subscriber from having to unsubscribe from events in order to avoid memory leaks.