Describes the action that caused a CollectionChanged event.
type TCollectionChangedAction = ( caAdded, caRemoved, caExtracted, caReplaced, caMoved, caReseted, caChanged );
The TCollectionChangedAction type exposes the following members.
An item was added to the collection.
An item in the collection was changed.
An item was removed from the collection without considering ownership.
An item was moved within the collection.
An item was removed from the collection.
An item was replaced in the collection.
The content of the collection changed dramatically.