Occurs when an AppDomain is about to be unloaded.
Assembly: mscorlib (in mscorlib.dll)
The EventHandler delegate for this event can perform any termination activities before the application domain is unloaded.
Each application domain that needs to perform processing when it is unloaded should register an event handler for this event. A shared event handler should not be used, because the EventHandler delegate does not identify the domain that is being unloaded.
This event is never raised in the default application domain.
Do not make assumptions about the thread the event is raised on. The event can be raised on a different thread than the one that called the Unload method.
To register an event handler for this event, you must have the required permissions, or a SecurityException is thrown.
For more information about handling events, see Handling and Raising Events.