add_collectionChanged(function(sender, e))
collectionChanged.add(function(sender, e))
remove_collectionChanged(function(sender, e))
collectionChanged.remove(function(sender, e))
    
            The event handler receives an argument of type AnnNotifyCollectionChangedEventArgs, which contains data that is related to this event.
AnnNotifyCollectionChangedEventArgs| Parameter | Type | Description | 
|---|---|---|
| sender | 'var' | The source of the event. | 
| e | # | The event data. |