#region 提取一个图层上的各类元素        [CommandMethod("BlockInLayerCAD")]        public void BlockInLayerCAD()        {            Document ed = Autodesk.AutoCAD.ApplicationServices.Application.DocumentManager.MdiActiveDocument;            Database db = HostApplicationServices.WorkingDatabase;            //PromptStringOptions pStringOption = new PromptStringOptions("\n 输入一个图层名");            //PromptResult layerName = pDocument.Editor.GetString(pStringOption);            List
    
      layerNames = new List
     
      ();            using (Transaction tran = db.TransactionManager.StartTransaction())            {                #region 获取图层名字                LayerTable pLayerTable = tran.GetObject(db.LayerTableId, OpenMode.ForRead) as LayerTable;                foreach (ObjectId pObjectId in pLayerTable)                {                    LayerTableRecord pLayerTableRecord = tran.GetObject(pObjectId, OpenMode.ForRead) as LayerTableRecord;                    layerNames.Add(pLayerTableRecord.Name);                }                #endregion                string layerName = layerNames[0];                string typeResult ="文字";                 TypedValue[] pTypedValue = new TypedValue[] { new TypedValue((int)DxfCode.LayerName, layerName) };                SelectionFilter pSelectFilter = new SelectionFilter(pTypedValue);                PromptSelectionResult pSelectionResult = ed.Editor.SelectAll(pSelectFilter);                SelectionSet pSelectionSet = pSelectionResult.Value;                Point3d startPoint = new Point3d();                Point3d endPoint = new Point3d();                if (typeResult != "全部")                {                    PromptPointOptions txtPoint = new PromptPointOptions("\n 选择两个点作为文字取值范围");                    txtPoint.Message = "\n 选择第一个点：";                    PromptPointResult txtStartPoint = ed.Editor.GetPoint(txtPoint);                    startPoint = txtStartPoint.Value;                    txtPoint.Message = "\n 选择第二个点：";                    PromptPointResult txtEndPoint = ed.Editor.GetPoint(txtPoint);                    endPoint = txtEndPoint.Value;                }                foreach (ObjectId selectedId in pSelectionSet.GetObjectIds())                {                    Entity pEntity = tran.GetObject(selectedId, OpenMode.ForRead) as Entity;                    switch (typeResult)                    {                        case "文字":                            if ((pEntity as MText) != null)                            {                                MText mText = pEntity as MText;                                if (mText.Location.X > startPoint.X && mText.Location.Y < startPoint.Y && mText.Location.X < endPoint.X && mText.Location.Y > endPoint.Y)                                {                                    Autodesk.AutoCAD.ApplicationServices.Application.ShowAlertDialog((pEntity as MText).Text);                                }                            }                            break;                    }                }                tran.Commit();            }        }#endregion