This event is fired when an object's attributes or geometry is updated.
[Visual Basic .NET] Public Event OnChange As OnChangeEventHandler
[C#] public event OnChangeEventHandler OnChange
[C++] HRESULT OnChange( IObject* obj );
obj is a parameter of type IObject
In the event that a feature should be deleted due to an OnChange event, it is not recommended that the event handler delete the feature itself. Instead, an exception should be thrown to the application, where it can be made responsible for deleting the feature.
The OnChange event is not fired during a Topology Validation for performance reasons as a large number of features may be changed during a Validate. In addition, features may be changed many times.