ArcEngine实现图层地物合并的简单方法

private IGeometry GetGeo(IFeatureLayer pFlyr)

{

IEnumGeometry pGeos = new EnumFeatureGeometryClass();

IEnumGeometryBind pGeosBind = pGeos as IEnumGeometryBind;

IFeatureSelection pflyrSelection = pFlyr as IFeatureSelection;

pflyrSelection.SelectFeatures(null,esriSelectionResultEnum.esriSelectionResultNew, false); pGeosBind.BindGeometrySource(null, pflyrSelection.SelectionSet);

pGeos.Reset();

IPolygonsPoly = new PolygonClass();

ITopologicalOperator pTopo = sPoly as ITopologicalOperator;

pTopo.ConstructUnion(pGeos);

pTopo.Simplify();

sPoly =pTopo as IPolygon;

pflyrSelection.Clear();

returnsPoly;

}

执行上面的代码段可以把图层上的所有实体合并。注意红色部分的那行代码，不写此行代码，pGeos
里的图形个数为0，最后得到的spoly是空。