ITopology Interface

Provides access to members that control a topology. Note: the ITopology interface has been superseded by ITopology2. Please consider using the more recent version.

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Members

	Name	Description
	AddClass	Add an object, feature, or attributed relationship class to the topology.
	Cache	The topology graph of the topology.
	ClusterTolerance	The cluster tolerance of the topology.
	DirtyArea	The dirty area polygon of the topology.
	FeatureDataset	The feature dataset that contains the topology.
	MaximumGeneratedErrorCount	The maximum number of errors to generate when validating a topology.
	RemoveClass	Remove an object, feature, or attributed relationship class to the topology.
	State	Indicates whether the topology is clean or not.
	TopologyID	The ID of the topology.
	ValidateTopology	Validate the specified area in the topology.

Classes that implement ITopology

Remarks

A Topology is a collection of simple feature classes within the same feature dataset that participate in topological relationships with a set of rules that govern those relationships.  Topologies can have multiple feature classes in the same topological role. A feature dataset may have multiple topologies but a feature class can only belong to one topology and only simple feature classes may participate in a topology.  Each topology has one associated topology graph. The topology graph is a planar representation of the geometries in the feature classes participating in a geodatabase topology.  If you need to access the topology graph directly for working with topology primitives such as edges and nodes, see the ITopologyGraph help.

When new features are created, edited or deleted, the topology is responsible for creating or modifying a dirty area that will encompass the envelope of the feature.  A dirty area is a special type of feature under which, the state of the topology is unknown.  Features that are covered by dirty areas can still be edited and queried, but their topological relationships cannot be guaranteed to be correct.  A dirty area must be validated in order to discover the topology of its underlying features and guarnatee their correctness.