In JScript, you can handle the events defined by another class, but you cannot define your own.
Managed Extensions for C++
protected: __event PropertyChanged
The event handler receives an argument of type containing data related to this event. The following PropertyChangedEventArgs properties provide information specific to this event.
Gets the name of the property that changed.
Target Platforms: Windows 98, Windows NT 4.0, Windows Millennium Edition, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003 family, Windows Vista, Windows Server 2008 family