C#将ESRI.Geometry.IGeometry多边形集合转为带面积的GeoJSON多边形对象集合

代码如下（异常在外部捕捉）：

                    Func<List<ESRI.ArcGIS.Geometry.IGeometry>, JArray> ConvertShapeWithArea = (lsGeo) =>
                    {
                        JArray aJArray = new JArray();
                        foreach (var pGeo in lsGeo)
                        {
                            JObject aJObject = new JObject(
                                new JProperty("shape", JObject.FromObject(GeometryFactory.CreateGeoJsonFromEsriGeometry(pGeo as ESRI.ArcGIS.Geometry.IPolygon))),
                                new JProperty("area", (pGeo as ESRI.ArcGIS.Geometry.IArea).Area)
                                );
                            aJArray.Add(JToken.FromObject(aJObject));
                        }
                        return aJArray;
                    };                    Func<List<