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I currently allow users to add a shape file in. From the shape file, allow the user to generate a new layer base on the polygons from the shape file's polygon they imported.

Generating the new polygon and putting them into my own layer is no longer a problem, however, I see the Area/Area_Length attribute to be different between my new and old polygon.

Only difference is i project-ed the Map's spatial reference to the new polygon, instead of using the layer's spatial reference.

Do you guys know if that is the reason behind the different attributes?


foreach (IPolygon polygon in polygons)
   //Need to project to the map spatial reference

   //Generate a new polygon
   newPolygon = new Polygon() as IPolygon;


   //Add the feature
   subcatchmentFeature = new SubcatchmentFeature(newPolygon);

Thanks and Regards Kev

share|improve this question
Are you referring to the differences in Area/Perimeter relationships between projected and unprojected data? – Dan Patterson May 17 '11 at 17:35

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