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I am trying to build procedure for finding gaps and convert the procedure steps in to code, but i am finding some difficulty, i wonder if someone can help me with it.

the steps i planned in seek of finding the gaps between polygons(which i have tried it using the toolbox and it works) are structured as the following:

  1. To find the gaps first i will merge all polygons in one polygon, but the resultant polygon still contain the gaps in it.
  2. i will build new polygon from the merged polygon by using only the outer perimeter points,since there is gaps, they will make an inner perimeter.
  3. i will subtract the new polygon from the merged polygon and the remaining will be only the gaps in forms of polygons, this can be done by using the erase tool

hope someone can provide me with the code syntax especially for step 2 and 3 in VBA (this is the internment required for this application)

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What GIS software are you using? – artwork21 Mar 26 '13 at 11:05
ArcGIS Desktop 9.2 web help is cited but is that what you are using? If so, can you add arcgis-9.2 as a tag, please? – PolyGeo Mar 26 '13 at 11:54
What have you tried so far? Have you tried using geoprocessing tools using IGeoprocessor interface? – Devdatta Tengshe Mar 26 '13 at 14:20
Have you looked at using Topology Tools? Setting a rule that no-gaps are allowed, then referencing the topology error information. – D.E.Wright Mar 30 '13 at 3:45

To do this I would create a rectangle (bounding box) polygon that surrounds your data in a new feature class and then Union it with your data. The gaps are where there are no attributes from your data - just those of the rectangle.

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