topic Re: How to determine which polygon contains the point x,y in ArcObjects SDK Questions

How to determine which polygon contains the point x,y

AnatoliiTerentiev — Thu, 14 Jun 2012 06:59:33 GMT

Dear Gurus!
I get point coordinates x,y by clicking on the axMapControl. How to determine which polygon of the feature layer contains the point ?
Thanks in advance!
(arcengine 2010 c# vs 2010)

Re: How to determine which polygon contains the point x,y

NeilClemmons — Thu, 14 Jun 2012 12:06:44 GMT

Do a spatial query using ISpatialFilter and IFeatureLayer.Search.

Re: How to determine which polygon contains the point x,y

AnatoliiTerentiev — Sat, 11 Dec 2021 23:03:55 GMT

Thank you very much!
I tried the following code:

       

 public IFeature getFeature(Point point, IGeoFeatureLayer geoFeatureLayer, IActiveView activeView, System.Double searchTolerance)
        {
            if (searchTolerance < 0 || point == null || geoFeatureLayer == null || activeView == null){return null;}
            IMap map = activeView.FocusMap;

            // Expand the points envelope to give better search results    
            ESRI.ArcGIS.Geometry.IEnvelope envelope = point.Envelope;
            envelope.Expand(searchTolerance, searchTolerance, false);

            ESRI.ArcGIS.Geodatabase.IFeatureClass featureClass = geoFeatureLayer.FeatureClass;
            System.String shapeFieldName = featureClass.ShapeFieldName;

            // Create a new spatial filter and use the new envelope as the geometry    
            ESRI.ArcGIS.Geodatabase.ISpatialFilter spatialFilter = new ESRI.ArcGIS.Geodatabase.SpatialFilterClass();
            spatialFilter.Geometry = envelope;
            spatialFilter.SpatialRel = ESRI.ArcGIS.Geodatabase.esriSpatialRelEnum.esriSpatialRelEnvelopeIntersects;
            spatialFilter.set_OutputSpatialReference(shapeFieldName, map.SpatialReference);
            spatialFilter.GeometryField = shapeFieldName;

            // Do the search
            ESRI.ArcGIS.Geodatabase.IFeatureCursor featureCursor = geoFeatureLayer.Search(spatialFilter, false);

            feature = featureCursor.NextFeature();

            return feature;
        }

But sometimes I getting the wrong result. In particular, when the point does not belong to any polygon - I get a certain polygon.
I need to get feature (region of republic - polygon) which contains the point.

Re: How to determine which polygon contains the point x,y

JoeHershman — Mon, 18 Jun 2012 09:48:50 GMT

You may want to try esriSpatialRelEnum.esriSpatialRelWithin instead of intersects

Good Luck

Re: How to determine which polygon contains the point x,y

AnatoliiTerentiev — Tue, 19 Jun 2012 03:34:34 GMT

Thanks!
This has helped!