I am trying to update some code from VB6 to VB.Net 2008 and have been generally successful. However, I came across an issue where, as it processes each polygon in the shapefile, it implements the following code.
Dim lngExtRing as Integer
lngExtRing = pPolygon.ExteriorRingCount - 1
ReDim pExtRings(pPolygon.ExteriorRingCount - 1) pPolygon.QueryExteriorRingsEx(pPolygon.ExteriorRingCount, pExtRings(0)) pExtRings(lngExtRing)
Once that code runs and you hover over the pExtRings portion of pExtRings(lngExtRing) for some polygons (not all), the first popup lists a ComObject but if you expand the plus, it indicates "Nothing".
I have run this on a shapefile that has 5 polygons and the two polygons that it fails on have negative areas. There are two ways that might resolve this, but I don't know how to implement either. One was to reverse the orientation if the area was negative, but I tried that on a different shapefile and it still failed on a polygon that did not have a negative area. The other, perhaps better, approach would be to implement the RepairGeometry class of ESRI.ArcGIS.DataManagementTools, but I have no clue on how to make it happen.
If anyone has any insight or examples of how to use RepairGeometry, I would certainly appreciate being enlightened.