ArcGIS Developer Help

ITopologyErrorFeature Interface

Provides access to members that return information about topology errors.

Product Availability

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

Members

	Name	Description
	DestinationClassID	ObjectClassID of the destination feature that created the topology error.
	DestinationOID	ObjectID of the destination feature that created the topology error.
	ErrorID	ID of the error.
	IsDeleted	Indicates if this topology error feature has been deleted.
	IsException	Indicates if topology error is an exception.
	OriginClassID	ObjectClassID of the origin feature that created the topology error.
	OriginOID	ObjectID of the origin feature that created the topology error.
	ShapeType	The geometry type of the topology error.
	TopologyRule	The topology rule that caused the topology error.
	TopologyRuleType	The Object Class for the row.

Classes that implement ITopologyErrorFeature

Classes	Description
TopologyErrorFeature	Esri Topology Error Feature object.

Remarks

The ITopologyErrorFeature interface provides access to the properties of error features in a topology. Topology errors are generated for each instance of a topology rule that is determined to be invalid during the validation process. Topology error features can also be deleted during the validation process.

Error features cannot be edited directly, so while you can use interfaces such as IFeature on a TopologyErrorFeature, calling methods such as IFeature::Value or IFeature::Store will fail. Topology errors have an associated geometry that can be used for rendering or fixing the error. Topology errors are persisted with the topology.

The only modification that can be made to an error feature is to mark it as an exception. An error feature that is marked as an exception will return True for its IsException property. Error features can be marked as exceptions by passing them to the ITopologyRuleContainer::PromoteToRuleException method, and those marked as exceptions can be demoted to error features by passing them to ITopologyRuleContainer::DemoteFromRuleException.

The following table shows the properties of error features created by violations of each rule. If an object ID or class ID is not applicable for a feature, a value of zero will be returned.

Name (esriTopologyRuleType value)	Origin OID	Origin ClassID	Destination OID	Destination ClassID	Error Feature Geometry (1)
Must Not Overlap (Polygons) esriTRTAreaNoOverlap	Yes	Yes	Yes	No	Polygon
Must Not Have Gaps esriTRTAreaNoGaps	No	Yes	No	No	Polyline
Must Not Overlap With (Polygons) esriTRTAreaNoOverlapArea	Yes	Yes	Yes	Yes	Polygon
Must Be Covered By Feature Class Of (Polygons) esriTRTAreaCoveredByAreaClass	Yes	Yes	No	Yes	Polygon
Must Cover Each Other esriTRTAreaAreaCoverEachOther	(2)	Yes	(2)	Yes	Polygon
Must Be Covered By esriTRTAreaCoveredByArea	Yes	Yes	No	Yes	Polygon
Boundary Must Be Covered By esriTRTAreaBoundaryCoveredByLine	Yes	Yes	No	Yes	Polyline
Area Boundary Must Be Covered By esriTRTAreaBoundaryCoveredByAreaBoundary	Yes	Yes	No	Yes	Polyline
Contains Point esriTRTAreaContainPoint	Yes	Yes	No	Yes	Polygon
Must Not Overlap (Lines) esriTRTLineNoOverlap	Yes	Yes	Yes	No	Polyline
Must Not Intersect esriTRTLineNoIntersection	Yes	Yes	Yes	No	Point, Polyline
Must Be Covered By Feature Class Of (Lines) esriTRTLineCoveredByLineClass	Yes	Yes	No	Yes	Polyline
Must Not Overlap With (Lines) esriTRTLineNoOverlapLine	Yes	Yes	Yes	Yes	Polyline
Must Be Covered By Boundary Of (Lines) esriTRTLineCoveredByAreaBoundary	Yes	Yes	No	Yes	Polyline
Must Not Have Dangles esriTRTLineNoDangles	Yes	Yes	No	No	Point
Must Not Have Pseudos esriTRTLineNoPseudos	Yes	Yes	Yes	No	Point
Must Not Self-Overlap esriTRTLineNoSelfOverlap	Yes	Yes	No	No	Polyline
Must Not Self-Intersect esriTRTLineNoSelfIntersect	Yes	Yes	No	No	Point, Polyline
Must Be Single Part esriTRTLineNoMultipart	Yes	Yes	No	No	Polyline (3)
Must Not Intersect Or Touch Interior esriTRTLineNoIntersectOrInteriorTouch	Yes	Yes	Yes	No	Point, Polyline
Endpoint Must Be Covered By esriTRTLineEndpointCoveredByPoint	Yes	Yes	No	Yes	Point
Must Be Covered By Boundary Of (Points) esriTRTPointCoveredByAreaBoundary	Yes	Yes	No	Yes	Point
Must Be Covered By Endpoint Of esriTRTPointCoveredByLineEndpoint	Yes	Yes	No	Yes	Point
Point Must Be Covered By Line esriTRTPointCoveredByLine	Yes	Yes	No	Yes	Point
Must Be Properly Inside esriTRTPointProperlyInsideArea	Yes	Yes	(4)	Yes	Point

(1) Every Topology rule can return an error that is a point geometry, because of the special case where the error geometry is completely collapsed. If a feature has all of its vertices within the cluster tolerance, it will collapse in on itself during validation and an error feature with a point geometry will be created.

(2) Error features caused by a "Must Cover Each Other" rule will have either an origin object ID or a destination object ID, but not both.

(3) An error feature will be created for each part of a polyline that contains multiple parts.

(4) If a point is on the boundary of a polygon from the destination class, an error feature will be created, and the polygon's object ID will be returned as the destination object ID. If a point does not touch any polygons of the destination class, no destination object ID will be returned.