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How Can I Ensure an Event Handler is Registered Only Once?

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2025-01-06 22:18:43660browse

How Can I Ensure an Event Handler is Registered Only Once?

Determining the Presence of an Event Handler

In handling interactions within an object's lifecycle, you may encounter scenarios where it's crucial to know if an event handler has been previously added to an object. While adding event handlers during property access can provide a convenient solution, it can lead to multiple registrations.

To address this concern, consider adopting a safer approach by first un-registering the event handler before attempting to register it again, even if the handler might not be initially present:

myClass.MyEvent -= MyHandler;
myClass.MyEvent += MyHandler;

This approach guarantees that the handler is registered only once, providing a cleaner and more efficient event management process.

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