Purge Method

WeakEventManager.Purge Method (Object, Object, Boolean)


Removes inactive listener entries from the data list for the provided source. Returns true if some entries were actually removed from the list.

Namespace:   System.Windows
Assembly:  WindowsBase (in WindowsBase.dll)

abstract Purge : 
        source:Object *
        data:Object *
        purgeAll:bool -> bool
override Purge : 
        source:Object *
        data:Object *
        purgeAll:bool -> bool


Type: System.Object

The source for events being listened to.

Type: System.Object

The data to check. This object is expected to be a WeakEventManager.ListenerList implementation.

Type: System.Boolean

true to stop listening to source, and completely remove all entries from data.

Return Value

Type: System.Boolean

true if some entries were actually removed; otherwise, false.

The Purge method has a default implementation that will remove all entries when data is a WeakEventManager.ListenerList.

Notes to Implementers:

If the underlying type for the Item is something other than WeakEventManager.ListenerList, or contains data beyond a WeakEventManager.ListenerList, you must override the Purge method. The override should provide purge behavior for the alternate type items list. Generally, the override should provide behavior without calling the base implementation. If a specific WeakEventManager.ListenerList still needs clearing, call Purge.

.NET Framework
Available since 3.0
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