Stops an observer from receiving any notifications from any object.
- iOS 2.0+
- macOS 10.0+
- tvOS 9.0+
- watchOS 2.0+
- Core Foundation
The notification center from which to remove observers.
The observer. This value must not be
If you no longer want an observer to receive any notifications, perhaps because the observer is being deallocated, you can call this function to unregister the observer from all the notifications for which it had previously registered.