public bool AddDataLayer(System.Data.DataTable dt, System.Drawing.Color dColor, System.Drawing.Color dSelectColor,int SymbolSize, ESRI.ArcGIS.ADF.Web.Display.Symbol.MarkerSymbolType SymbolType)
        {
            bool bResult = false;
            ESRI.ArcGIS.ADF.Web.DataSources.Graphics.MapFunctionality mf = (ESRI.ArcGIS.ADF.Web.DataSources.Graphics.MapFunctionality)m_map.GetFunctionality(0);
            if (mf == null) return bResult;
            //如果圖層已存在，則返回
            ESRI.ArcGIS.ADF.Web.DataSources.Graphics.MapResource mr = (ESRI.ArcGIS.ADF.Web.DataSources.Graphics.MapResource)mf.Resource;
            string[] layerIds;
            string[] layerNames;
            mf.GetLayers(out layerIds, out layerNames);
            for (int i = 0; i < layerIds.Length; i++)
            {
                if (layerNames[i] == dt.TableName) return bResult;
            }

            ESRI.ArcGIS.ADF.Web.Display.Graphics.FeatureGraphicsLayer graphicslayer = new ESRI.ArcGIS.ADF.Web.Display.Graphics.FeatureGraphicsLayer(FeatureType.Point);
            System.Data.DataColumn cl0 = new System.Data.DataColumn("編碼", typeof(System.String));
            System.Data.DataColumn cl1 = new System.Data.DataColumn("名稱", typeof(System.String));
            graphicslayer.Columns.Add(cl0);
            graphicslayer.Columns.Add(cl1);
            graphicslayer.TableName = dt.TableName;
            
            for (int i = 0; i < dt.Rows.Count; i++)
            {
                double x = System.Convert.ToDouble(dt.Rows[i]["PosX"]);
                double y = System.Convert.ToDouble(dt.Rows[i]["PosY"]);
                if (x == null) x = 0;
                if (y == null) y = 0;
                if ((x > 0) && (y > 0))
                {
                    ESRI.ArcGIS.ADF.Web.Geometry.Point p = new ESRI.ArcGIS.ADF.Web.Geometry.Point(x, y);
                    System.Data.DataRow lr = graphicslayer.Add(p);
                    lr["名稱"] = dt.Rows[i]["Name"];
                    lr["編碼"] = dt.Rows[i]["Code"];
                }
            }
            
            mr.Graphics.Tables.Add(graphicslayer);
            bResult = true;
            return bResult;
        }