CAD—鼠标悬浮显示信息

    在CAD2006中，可以借用Editor的两个事件来实现鼠标的悬浮显示信息的功能，即ToolTip。这两个事件都可以实现ToolTip的功能。具体代码如下：

        Editor ed = Application.DocumentManager.MdiActiveDocument.Editor;
        #region IExtensionApplication 成员

        public void Initialize()
        {
            MyToolTip();
        }

        public void Terminate()
        {
            //throw new System.Exception("The method or operation is not implemented.");
        }

        private void MyToolTip()
        {
            ed.PointMonitor +=new PointMonitorEventHandler(ToolTip);
            ed.PointFilter +=new PointFilterEventHandler(ed_PointFilter);
        }

        private void ToolTip(object sender, PointMonitorEventArgs e)
        {
            Database db = HostApplicationServices.WorkingDatabase;
            FullSubentityPath[] paths = e.Context.GetPickedEntities();

            if (paths.Length > 0)
            {
                FullSubentityPath fsPath = paths[0];
                using (Transaction trans = db.TransactionManager.StartTransaction())
                {
                    ObjectId entId = fsPath.GetObjectIds()[0];
                    Entity ent = trans.GetObject(entId, OpenMode.ForRead) as Entity;
                    e.AppendToolTipText("PointMonitor事件\n实体是：" + ent.GetType().ToString()); 
                    trans.Commit();
                }
            }
            else
            {
                e.AppendToolTipText("请选择图元");
            }
        }

               private void ed_PointFilter(object sender, PointFilterEventArgs e)
               {
                   Database db = HostApplicationServices.WorkingDatabase;
                   FullSubentityPath[] full = e.Context.GetPickedEntities();
                   if (full.Length > 0)
                   {
                      FullSubentityPath fSon = full[0];
                      ObjectId[] ids = fSon.GetObjectIds();
                      ObjectId id = ids[0];
                      using (Transaction trans = db.TransactionManager.StartTransaction())
                      {
                          Entity ent = trans.GetObject(id, OpenMode.ForRead) as Entity;
                          e.Result.ToolTipText = "PointFilter事件\nID:" + id.ToString();  
                      }
                  }  
               }
          #endregion