This message maps the index of an item to a unique identifier (ID).
To send this message, call the SendMessage function.
List-view controls internally track items by index. This can present problems because indexes can change during the control's lifetime.
The list-view control can tag an item with an ID when the item is created. You can use this ID to guarantee uniqueness during the lifetime of the list-view control.
|In a multithreaded environment, the index is only guaranteed on the thread that hosts the list-view control, not on background threads.|