ArcObjects Library Reference (EditorExt)  

MapTopology Class

The current map topology.

MapTopology is a non-creatable object. References to non-creatable objects must be obtained through other objects.

Product Availability

Available with ArcGIS Desktop.


A MapTopology is a topology that is temporarily created in a map document for use with the Topology Edit tool and Topology Edit tasks.

Supported Platforms



Interfaces Description
IMapTopology Provides access to a Map topology.


A MapTopology contains no topology rules and cannot be saved outside of the map document. It is accessed through the TopologyExtension and cannot be co-created.

Feature classes have to be explicitly added to the MapTopology in order to be considered. Once added to the MapTopology the references to the Feature Classes are persisted with the MapTopology in the MXD document. 

Only feature classes that support ITopologyClass can be added to a MapTopology. This means that network classes, annotation, dimensions and coverage feature classes cannot be added to a MapTopology. The topology primitives (TopologyNode, TopologyEdge) can then be accessed through the TopologyGraph. (Please refer to ITopologyGraph interface help topic for more details)