Can I get the list of entities which were selected before the current command started (in .NET)?

By Marat Mirgaleev

Issue

If the user had selected some entities and then started my command, can I find out which entities were selected?

Solution

Yes, it is possible, if the PICKFIRST system variable is set to 1 and your command has the UsePickSet flag set.

The sample below shows a command that prints out the list of selected entities.

[CommandMethod("LiPS", CommandFlags.UsePickSet)]      public static void ListPreSelected()      {        Document doc = Application.DocumentManager.MdiActiveDocument;        PromptSelectionResult selectionResult =                                               doc.Editor.SelectImplied();        if (selectionResult.Status == PromptStatus.OK)        {          using (Transaction tr =                       doc.Database.TransactionManager.StartTransaction())          {            SelectionSet currentlySelectedEntities =                                                    selectionResult.Value;            foreach (ObjectId id                      in currentlySelectedEntities.GetObjectIds())            {              Entity ent = tr.GetObject(id, OpenMode.ForRead) as Entity;              doc.Editor.WriteMessage("n..." + ent.ToString());            }          }        }        else          doc.Editor.WriteMessage("n...SelectionResult.Status="                                     + selectionResult.Status.ToString());      } // ListPreSelected()