ArcObjects Library Reference (GeoDatabase)

ITopologyClassEvents Interface

Provides access to events that occur with a topology class.

Product Availability

Available with ArcGIS Engine, ArcGIS Desktop, and ArcGIS Server.

When To Use

Use ITopologyClassEvents for building ClassExtensions when you don't want to rely on catching the ITopologyExtensionEvents OnValidate event. This is handy when you need to implement a geodatabase-level customization that will not be application specific, i.e. dependent upon ArcMap and the Topology extension.

Members

		Description
	OnValidate	This event is fired when the topology containing the class is validated.

CoClasses that implement ITopologyClassEvents

CoClasses and Classes	Description
TopologyClassEvents	Helper coclass for working with the outbound interface ITopologyClassEvents.
TopologyClassEventsListener (esriSystemUtility)	Helper coclass to provide ITopologyClassEvents support to the C++ API.

Remarks

The ITopologyClassEvents interface provides access to the OnValidate event which is fired each time a dirty area is validated in the topology in which the class is participating. The event returns an IGeometry object corresponding the area that was validated.

ITopologyClassEvents can be listened to by class extensions or custom objects when relying on the ITopologyExtensionEvents::OnValidate event isn't ideal. This is useful when you need to implement a geodatabase-level customization that will not be application specific, i.e. dependent upon ArcMap and the Topology extension.