Public Event MediaOpened As RoutedEventHandler

Dim instance As MediaElement
Dim handler As RoutedEventHandler

AddHandler instance.MediaOpened, handler

public event RoutedEventHandler MediaOpened

public:
 event RoutedEventHandler^ MediaOpened {
    void add (RoutedEventHandler^ value);
    void remove (RoutedEventHandler^ value);
}

JScript does not support events.

<object MediaOpened="RoutedEventHandler" .../>