Thanks John for the workaround tip!
-I had been working on this for Shimin, and sent a test case through to ESRI support, highlighting that this issue went beyond just the Help documentation, as implied by the subject header of NIM066487. Anyway, just tried your tip in my .Net equivalent (included below), and it works a treat. (Needless-to-say the subject header for NIM066487 may need to be changed)
Thanks very much
Allison,
ESRI Australia
Dim mxDoc As IMxDocument = m_application.Document
Dim pMap As IMap = mxDoc.FocusMap
Dim cliplayer As IFeatureLayer = pMap.Layer(0)
'get the features in the clipLayer to construct a geometry to be assigned to the IMap.ClipGeometry
Dim pFeatCursor As IFeatureCursor = cliplayer.Search(Nothing, False)
Dim feature As IFeature = pFeatCursor.NextFeature
'loop through the features to construct a geometry to be assigned ti the IMap:ClipGeometry
Dim counter As Integer = 0
Dim topoOperator As ITopologicalOperator
Dim unionGeometry As IGeometry = Nothing
While (feature) IsNot Nothing
Dim geometry As ESRI.ArcGIS.Geometry.IGeometry = feature.Shape
If (counter = 0) Then
topoOperator = feature.ShapeCopy
counter = counter + 1
Else
unionGeometry = topoOperator.Union(feature.ShapeCopy)
topoOperator = CType(unionGeometry, ITopologicalOperator)
End If
feature = pFeatCursor.NextFeature
End While
Dim mco As IMapClipOptions = CType(pMap, IMapClipOptions)
mco.ClipType = esriMapClipType.esriMapClipMapExtent
If (unionGeometry) IsNot Nothing Then
pMap.ClipGeometry = unionGeometry
End If
mxDoc.ActiveView.Refresh()