Adds an entry to the notification center's dispatch table with an observer, a selector, and an optional notification name and sender.
An object registering as an observer.
A selector that the notification center sends notificationObserver to notify when posting the notification.
The name of the notification for which to register the observer; that is, only notifications with this name are delivered to the observer. When nil, the notification center doesn't use a notification's name to decide whether to deliver it to the observer.
The object whose notifications the observer wants to receive; that is, only notifications sent by this sender are delivered to the observer. When nil, the notification center doesn't use a notification's sender to decide whether to deliver it to the observer.
This method calls addObserver:selector:name:object:suspensionBehavior:, passing NSNotificationSuspensionBehaviorCoalesce for suspensionBehavior.
Removes matching entries from the receiver's dispatch table.