public void ValidateTopology(ITopology topology, IEnvelope envelope)

{

    // Get the dirty area within the provided envelope.

    IPolygon locationPolygon = new PolygonClass();

    ISegmentCollection segmentCollection = (ISegmentCollection)locationPolygon;

    segmentCollection.SetRectangle(envelope);

    IPolygon polygon = topology.get_DirtyArea(locationPolygon);

    // If a dirty area exists, validate the topology.

    if (!polygon.IsEmpty)

    {

        // Define the area to validate and validate the topology.

        IEnvelope areaToValidate = polygon.Envelope;

        IEnvelope areaValidated = topology.ValidateTopology(areaToValidate);

    }

}

public void AddRuleToTopology(ITopology topology, esriTopologyRuleType ruleType,

String ruleName, IFeatureClass originClass, int originSubtype, IFeatureClass

destinationClass, int destinationSubtype)

{

    // Create a new topology rule.

    ITopologyRule topologyRule = new TopologyRuleClass();

    topologyRule.TopologyRuleType = ruleType;

    topologyRule.Name = ruleName;

    topologyRule.OriginClassID = originClass.FeatureClassID;

    topologyRule.AllOriginSubtypes = false;

    topologyRule.OriginSubtype = originSubtype;

    topologyRule.DestinationClassID = destinationClass.FeatureClassID;

    topologyRule.AllDestinationSubtypes = false;

    topologyRule.DestinationSubtype = destinationSubtype;

    // Cast the topology to the ITopologyRuleContainer interface and add the rule.

    ITopologyRuleContainer topologyRuleContainer = (ITopologyRuleContainer)

    topology;