写扩展数据的问题

李毛毛

 AddXData(lwPolyLine, i + 1, "polyId");
 //写扩展数据
        public Entity AddXData(Entity ent, Object obj, string regapptablename)
        {
            ObjectId objId = ent.ObjectId;
            Database db = HostApplicationServices.WorkingDatabase;
            Entity retEntity;
            using (Transaction trans = db.TransactionManager.StartTransaction())
            {
                retEntity = (Entity)trans.GetObject(ent.ObjectId, OpenMode.ForWrite);
                RegAppTable apptbl = (RegAppTable)trans.GetObject(db.RegAppTableId, OpenMode.ForWrite);
                if (!apptbl.Has(regapptablename))
                {
                    RegAppTableRecord appTblRcd = new RegAppTableRecord();
                    appTblRcd.Name = regapptablename;
                    apptbl.Add(appTblRcd);
                    trans.AddNewlyCreatedDBObject(appTblRcd, true);
                }
                ResultBuffer resBuf = new ResultBuffer();
                resBuf.Add(new TypedValue((int)DxfCode.ExtendedDataRegAppName, regapptablename));
                resBuf.Add(new TypedValue((int)DxfCode.ExtendedDataAsciiString, obj));
                ent.XData = resBuf;
                trans.Commit();
            }
            return retEntity;
        }
保存之后关闭再打开，为什么扩展数据里就没有了呢？？

雪山飞狐_lzh

子函数里没找到错，这里改下试试 

AddXData(lwPolyLine, (i + 1).ToString, "polyId");

李毛毛

TypedValue[] fillist = new TypedValue[] { (new TypedValue((int)DxfCode.Start, "LWPolyline"))};//,new TypedValue(8,"外围轮廓线") };
                SelectionFilter filter = new SelectionFilter(fillist);
                PromptSelectionResult lwPolyRes = ed.SelectAll(filter);
                TypedValue[] fillist1 = new TypedValue[] { (new TypedValue((int)DxfCode.Start, "olyline"))};//, new TypedValue(8, "外围轮廓线") };
                SelectionFilter filter1 = new SelectionFilter(fillist1);
                PromptSelectionResult polyRes = ed.SelectAll(filter1);
                if (lwPolyRes.Status == PromptStatus.OK&&polyRes.Status==PromptStatus.OK)
                {
                    SelectionSet lwPolySet = lwPolyRes.Value;
                    int lwPolyCount = lwPolySet.Count;
                    Polyline lwPolyLine = new Polyline();
                    SelectionSet polySet = polyRes.Value;
                    int polyCount = polySet.Count;
                }
本来想设置断点在第一行的，可是它不执行，直接跑到下面去了，跑就跑呗，执行过的代码还看不到执行结果。是不是vs2005的问题啊？？？

sieben

retEntity = (Entity)trans.GetObject(ent.ObjectId, OpenMode.ForWrite);

------------------

这个函数好搞笑

李毛毛

搞不懂，不对吗？

雪山飞狐_lzh

哈哈

retEntity == ent;

sieben

Entity ent,

retEntity = (Entity)trans.GetObject(ent.ObjectId, OpenMode.ForWrite);

你的ent类型是Entity,说明若是已存在的实体,已经打开了,你在这里又再打开,你这一行若没有问题也是多余了,你直接使用ent即可,可能前面是只读打开,那么你升级为可写打开即可,若Entity ent是个新建实体(还没提交到数据库),你这一行应该会报错.

雪山飞狐_lzh

OK,贴个相关的扩展函数，调用方式：

1/简单的例子

    ent.UpgradeOpen(() => ent.ColorIndex = 3) ;

2/较为复杂的例子

                BlockTable.UpgradeOpen
                (
                    () =>
                    {
                        BlockTableRecord btr = new BlockTableRecord();
                        btr.Name = name;
                        id = BlockTable.Add(btr);
                        Transaction.AddNewlyCreatedDBObject(btr, true);
                    }
                );

 

 

        public static void UpgradeOpen<T>(this T obj, Action action) where T : DBObject
        {
            if (obj.IsNotifyEnabled)
            {
                bool b = obj.IsWriteEnabled;
                obj.UpgradeFromNotify();
                action();
                obj.DowngradeToNotify(b);
            }
            else if (obj.IsWriteEnabled)
            {
                action();
            }
            else
            {
                obj.UpgradeOpen();
                action();
                obj.DowngradeOpen();
            }
        }

李毛毛

哦，这样啊.我一直以为

retEntity == ent;

跟

retEntity = (Entity)trans.GetObject(ent.ObjectId, OpenMode.ForWrite);

一样呢？我习惯这样写了，现在才知道。谢谢谢谢...我再试试

李毛毛

飞狐，我如果把写过扩展数据的dwg文件，复制一份，再进行操作，那是不是原版和复制版都有扩展数据啊？？？怎么才能看到它的扩展数据捏