将多个几何对象合并（IGeometry）

        public static IGeometry UnionTwoGeometries(IGeometry geometryA, IGeometry geometryB)         {             try             {                 ITopologicalOperator pTopologicalOperator = geometryA as ITopologicalOperator;                 return pTopologicalOperator.Union(geometryB);             }             catch (Exception ex)             {                 return null;             }         }

有时可能会报错：

报错，异常来自“HRESULT:0x80040218”,该错误为输入图形未经简化处理所至，完善try中的代码，将其修改为

try

{

ITopologicalOperator pTopologicalOperator = geometryA as ITopologicalOperator;

pTopologicalOperator.Simplify();

(geometryB as ITopologicalOperator).Simplify();

return pTopologicalOperator.Union(geometryB);

}