AutoCAD ObjectARX实现多边形图层闭合检查

 /// <summary>
        /// 多边形图层闭合检查
        /// </summary>
        /// <param name="pLayerName"></param>
        public void PolineToPolygon_BasedLayer(string pLayerName)
        {
            if (CheckRegistry() == false)
            {
                MessageBox.Show("模块未注册，请先注册该模块！获取帮助:刘刚(电话:15928111254)!");
                return;
            }
            try
            {
                AcadApplication pApp = (AcadApplication)Autodesk.AutoCAD.ApplicationServices.Application.AcadApplication;
                AcadDocument pAppDoc = (AcadDocument)pApp.ActiveDocument;
                Database db = Autodesk.AutoCAD.ApplicationServices.Application.DocumentManager.MdiActiveDocument.Database;



                //记录当前图层,并设置当前图层为pLayerName
                ObjectId pOldClayer = db.Clayer;
                using (Transaction trans = db.TransactionManager.StartTransaction())
                {

                    LayerTable lt = (LayerTable)trans.GetObject(db.LayerTableId, OpenMode.ForWrite);
                    if (lt.Has(pLayerName) == false)
                    {
                        return;
                    }

                    LayerTableRecord ltr = (LayerTableRecord)trans.GetObject(lt[pLayerName], OpenMode.ForWrite);
                    LayerTableRecord curLtr = (LayerTableRecord)trans.GetObject(db.Clayer, OpenMode.ForRead);

                    db.Clayer = ltr.ObjectId;
                    trans.Commit();
                }
                
                
                
                
                
                
                
                
                
                Autodesk.AutoCAD.DatabaseServices.TransactionManager tm = db.TransactionManager;
                Autodesk.AutoCAD.EditorInput.Editor ed = Autodesk.AutoCAD.ApplicationServices.Application.DocumentManager.MdiActiveDocument.Editor;
                TypedValue[] pValue = new TypedValue[1];
                pValue[0] = new TypedValue((int)DxfCode.LayerName, pLayerName);
                SelectionFilter filter = new SelectionFilter(pValue);
                PromptSelectionResult res = ed.SelectAll(filter);


                List<Polyline> pLineList = new List<Polyline>();
                List<Point2d> pStartPointList = new List<Point2d>();
                List<Point2d> pEndPointList = new List<Point2d>();
                Polyline pL = null;
                Point2d pS;
                Point2d pE;
                if (res.Value != null)