IPolygon4 pMergerPolygon=pFeature.Shape as IPolygon4;

IGeometryBag pOutGeometryBag = pMergerPolygon.ExteriorRingBag;  //获取外部环

IGeometryCollection pOutGmtyCollection = pOutGeometryBag as IGeometryCollection;

for (int i = ; i < pOutGmtyCollection.GeometryCount; i++)  //对外部环遍历

{

    IGeometry pOutRing = pOutGmtyCollection.get_Geometry(i); //外部环

    IGeometryBag pInteriotGeometryBag = pMergerPolygon.get_InteriorRingBag(pOutRing as IRing);  //获取内部环

    IGeometryCollection pInteriorGeometryCollection = pInteriotGeometryBag as IGeometryCollection;

    for (int j = ; j < pInteriorGeometryCollection.GeometryCount; j++)

    {

         IGeometry pInteriorGeometry = pInteriorGeometryCollection.get_Geometry(j);

         //pInteriorGeometry即为多边形的内部环

    }

}