When Is The Best Time to Unsubscribe Events in A Page or A Templated Control?

[ShimizuTheLotus]

Hi community! I'm new to coding with Microsoft.UI.Xaml, and I'm trying to make some apps. I heard that if not unsubscribing a event, it would cause memory leaking.

Microsoft Learn said that I should unsubscribe the events before "before you dispose of a subscriber object", but how can I know when I don't need these events again? I tried unsubscribing in a finalizer, but when the unscribing action was invoked, the debugger will throw an exception telling me the object was already disposed. I did the same in WPF but it won't have that exception. Now I have no idea when to unsubscribe them.

Plus, if there's an anonymous function, how can I unsubscribe it? Or there's no need to unsubscribe them all?

Please help!