vb.net arcobjects validate topology ITopologyExtension and esriTEEventHint not declared

Question

I am trying to use arcobjects with vb.net to validate a topology (already defined). I am caught even when I use the sample provided by ESRI.

The code I use for accessing a topology is:

Dim topoUiD As UID = New UIDClass
topoUiD.Value = "esriEditorExt.TopologyExtension"
Dim topologyExt As ITopologyExtension = CType(m_application.FindExtensionByCLSID(topoUiD),      ITopologyExtension)
Dim topology As ITopology
topology = CType(topologyExt.CurrentTopology, ITopology)

The code I use for selecting errors is as follow:

topologyExt.ClearActiveErrors(esriTEEventHint.esriTENone)
topologyExt.DelayEvents(True)
While Not ((topoError = eErrorFeat.Next) Is Nothing)
    topologyExt.AddActiveError(topoError, esriTEEventHint.esriTENone)
End While
topologyExt.DelayEvents(False)

I get the following errors:

(1) ITopologyExtension is not declared

(2) esriTEEventHint is not declared

I want to check what is missing in the code? Is it the arcObjects library, if yes, what library should be used.

I am a beginner in arcObjects. Please help me on it, thanks.

Answer 1

iTopologyExtension interface is part of the ESRI.ArcGIS.EditorExt namespace, so you need to import this namespace at the top of your module (and also check it is added to references):

Import ESRI.ArcGIS.EditorExt

Or if you don't want to import, just reference iTopologyExtension in full:

Dim pTopoExt As ESRI.ArcGIS.EditorExt.ITopologyExtension

I think esriTEEventHint may be recognised when you import the namespace (although I could be wrong).