AutoCAD DevBlog

Copy a leader using Visual LISP

By Wayne Brill

Recently I had a case where the question was how to create a new leader based on an existing leader using AutoLISP. Here is an example that I came up with. When you run this example you select a leader and the MText annotation for the leader. After you run the function you will need to move the Leader manually to see that there are are two leaders at the same location.

Another way to do this would be to use the Copy method and set the annotation property. This example is just getting the points from the existing leader, the MText, and then creating a new Leader at the same location.   

 

(defun C:copyLeaderTest (/ vla_ldr vla_mtx coords numberOfPoints
           arrayForPoints points attachPointFromExistingMText
           textForMText widthForMText insertioinPointForMText
           acadObj doc modelSpace newMText
               drawingDirectionForMText newLeader verticalTextPosition)

  (vl-load-com)
  (setvar "osmode" 0)
  (setvar "orthomode" 0)

  ; Get Leader and MText
  (while (setq ss1 (ssget (list (cons -4 "<OR")
    (cons 0 "LEADER") (cons 0 "MTEXT")(cons -4 "OR>"))))

   ; Ensure selection set has two entities
  (if (/= (sslength ss1) 2)
    (alert "Select 1 MText and 1 leader.")
    ; Have a Leader and MText get the ActiveX Object
    (progn
      (if (= (cdr (assoc 0 (entget (ssname ss1 0)))) "LEADER")
    (setq vla_ldr (vlax-ename->vla-object (ssname ss1 0))
          vla_mtx (vlax-ename->vla-object (ssname ss1 1))
    )
    (setq vla_ldr (vlax-ename->vla-object (ssname ss1 1))
          vla_mtx (vlax-ename->vla-object (ssname ss1 0))
    )
      )

         
      ; Get the coordinates from the existing leader
      ; and make an array of doubles
      (setq coords (vlax-get vla_ldr 'Coordinates))
      (setq numberOfPoints (1- (length coords)))
      (setq arrayForPoints (cons 0 numberOfPoints))
      (setq points (vlax-make-safearray vlax-vbDouble
                             arrayForPoints))
      (vlax-safearray-fill points coords)
     
    ; Store the current attachmentpoint of the existing MText 
    (setq attachPointFromExistingMText (vla-get-attachmentpoint vla_mtx))

    ; change the attachmentPoint for existing leader to Top Left
    ; This is will make the insertion point correct for the new MText
    (vla-put-AttachmentPoint vla_mtx acAttachmentPointTopLeft)
   
    (setq textForMText (vla-get-TextString vla_mtx))
    (setq widthForMText (vla-get-width vla_mtx))
    (setq insertioinPointForMText (vla-get-insertionpoint vla_mtx))

    ; Get modelspace and add the new MText
    (setq acadObj (vlax-get-acad-object))
    (setq doc (vla-get-ActiveDocument acadObj))
    (setq modelSpace (vla-get-ModelSpace doc)) 
    (setq newMText (vla-AddMText modelSpace
          insertioinPointForMText widthForMText textForMText))

    (vla-put-AttachmentPoint newMText attachPointFromExistingMText)

    ; make the attachmentPoint what it was
    (vla-put-AttachmentPoint vla_mtx attachPointFromExistingMText)

    (setq drawingDirectionForMText (vla-get-drawingdirection vla_mtx))
    (vla-put-drawingdirection newMText drawingDirectionForMText)
     
    ;; Create the leader object in model space
    (setq newLeader (vla-AddLeader modelSpace points newMText acLineWithArrow))

    (setq verticalTextPosition(vla-get-VerticalTextPosition vla_ldr))
    (vla-put-VerticalTextPosition newLeader verticalTextPosition)
     
    (vla-put-ArrowheadBlock
        newLeader
        (vla-get-ArrowheadBlock vla_ldr)
    )

    (vla-put-layer newLeader (vla-get-layer vla_ldr))
    (vla-put-layer newMText (vla-get-layer vla_mtx))

   ; (vla-Erase vla_ldr)
   ; (vla-Erase vla_mtx)

     )
  )
)

  (princ)
)

Opening a P&ID Drawing that was edited offline (avoiding the Update dialog)

By Wayne Brill

A drawing that was edited offline has to be re-inserted (merged) into the project. Plant drawings contain subset of project database (BLOB as SQL database). Plant also a knows whether the drawing was saved in the current project or not. If drawing was not saved in the current project, the BLOB has to be merged into the project.

There are several API to handle this situation:

Project.IsDrawingOutOfSync(string dwgname, Database db) – tells whether AcDbDatabase is in sync with project database

Project.UpdatePnPDrawing(Database db, string dwgname, ref PnPSyncConflicts conflicts) – merge blob into project database.

C# example:

[CommandMethod("testOpen", CommandFlags.Session)]

public void testOpen()

{

    string strDwgPath;

    Database db = new Database(false, true);

 

    Project currentProject =

        PlantApp.CurrentProject.ProjectParts["PnId"];

    DataLinksManager dlm =

                     currentProject.DataLinksManager;

 

    // get project drawing 

    PnPProjectDrawing pnp_dwg =

        currentProject.GetDwgFileByName

        ("C:\\MyProject\\PID DWG\\PumpAnlage.dwg");

 

    // use resolved path

    strDwgPath = pnp_dwg.ResolvedFilePath;

 

 

    db.ReadDwgFile(strDwgPath,

                FileShare.ReadWrite, false, null);

    // tell DLM to manage drawing database.

    //(Documents are automatically enlisted

    //when they are opened in editor)

    dlm.EnlistDrawing(db);

    // dispose will unelist it

 

    if (currentProject.IsDrawingOutOfSync

                              (strDwgPath, db))

    {

 

        PnPSyncConflicts conflicts = null;

        currentProject.UpdatePnPDrawing

                (db, strDwgPath, ref conflicts);

        // tell DLM that drawing related data has to

        // be saved in the project database.

        // otherwise, DLM will not save drawing sync

        // timestamp causing out-of-sync

        // situation on drawing open

      DataLinksManager.DatabaseToForceSaveComplete

                                             = db;

        try

        {

            db.SaveAs(strDwgPath, DwgVersion.Current);

        }

        catch (System.Exception ex)

        {

 

        }

        finally

        {

          DataLinksManager.DatabaseToForceSaveComplete

                                               = null;

 

        }

    }

 

 

    db.CloseInput(true);

    db.Dispose();

 

    DocumentCollection acDocMgr =

                         Application.DocumentManager;

 

    Document acDoc = acDocMgr.Open(strDwgPath, false);

 

    AcadDocument anAcadDoc =

               (AcadDocument)acDoc.GetAcadDocument();

    // if(!anAcadDoc.Saved)

        anAcadDoc.Save();

 

}

Run PlantPipeSupportConvert command using acedCmd

By Wayne Brill

There is not an API to convert an AutoCAD object to a Plant 3D pipe support like the PlantPipeSupportConvert command does. You can run the command from your code however. This c# example creates a command that has the user select the pipe and an AutoCAD entity to be used as the support. The location of the support is the mid point of the selected pipe. The Plant 3D API is used to get the length of the pipe from the database and it is used to calculate the mid point. The PlantPipeSuportConvert command takes a point for the pipe. (It uses an an input point monitor to get the pipe at that point). 

  Download Plant_3D_PipeSupportConvert

Note: Put the Plant_3D_Test_wB.dll in the PLNT3D folder to avoid errors about missing references. (this issue has been reported to Plant 3D engineering)

C:\Program Files\Autodesk\AutoCAD 2014\PLNT3D

 

Here is the command:

[CommandMethod("PipeSupConvert")]

public void myPlantPipeSuppportConvert()

{

    Document docDocument =

       AcadApp.DocumentManager.MdiActiveDocument;

    Database dbDatabase = docDocument.Database;

    Editor ed = docDocument.Editor;

    PromptEntityOptions pmtEntOpts =

        new PromptEntityOptions

("\nSelect a Pipe to connect to new Support : ");

    PromptEntityResult pmtEntRes =

                        ed.GetEntity(pmtEntOpts);

 

    if (pmtEntRes.Status == PromptStatus.OK)

    {

        Autodesk.AutoCAD.DatabaseServices.

            TransactionManager tmTranMan =

                  dbDatabase.TransactionManager;

        Transaction trans = null;

        ObjectId oidPipeId = pmtEntRes.ObjectId;

        try

        {

            Project currentProject =

                PlantApp.CurrentProject.

                         ProjectParts["Piping"];

            DataLinksManager dlm =

                currentProject.DataLinksManager;

            PnPDatabase pnpdb =

                           dlm.GetPnPDatabase();

 

            // will use this with acedCmd to

            // send the command

            ResultBuffer rb = new ResultBuffer();

 

            trans = tmTranMan.StartTransaction();

            Pipe supP3DPipe = trans.GetObject

           (oidPipeId, OpenMode.ForRead) as Pipe;

            if (supP3DPipe == null)

            {

                ed.WriteMessage

("\n   Selected entity is not a Plant 3D Pipe");

            }

            else

            {

                // Output the ObjectId of the

                //Pipe for check purposes

                //  ed.WriteMessage

 //("\n   ObjectId of the Pipe : {0}", oidPipeId);

 

                // Get Matrix3d of the selected

                // pipe to extract its Xaxis

                Matrix3d suppM3D =

                        ((Entity)supP3DPipe).Ecs;

 

                // Get the RowId of the Pipe in

                // the Plant 3D project database

                int iPipeRowId =

                    dlm.FindAcPpRowId(oidPipeId);

 

                // Get the corresponding PnPRow

                // of the Pipe

                PnPRow ppRow =

                         pnpdb.GetRow(iPipeRowId);

 

                // Get the insertion point of

                // the selected Pipe

                Point3d p3dPipePosition =

                    new Point3d(

            Convert.ToDouble(ppRow["Position X"]),

            Convert.ToDouble(ppRow["Position Y"]),

           Convert.ToDouble(ppRow["Position Z"]));

 

                // Get the Pipe length from the

                // Plant 3D project database

                double dPipeLength =

               Convert.ToDouble(ppRow["Length"]);

 

                // Get the position of the

                // middle of the selected Pipe

                Point3d p3dSupportInsertionPoint =

                    new Point3d(

                 p3dPipePosition.X + dPipeLength *

             suppM3D.CoordinateSystem3d.Xaxis.X / 2,

                 p3dPipePosition.Y + dPipeLength *

             suppM3D.CoordinateSystem3d.Xaxis.Y / 2,

                 p3dPipePosition.Z + dPipeLength *

            suppM3D.CoordinateSystem3d.Xaxis.Z / 2);

 

                // Commit the transaction have

                // all the data now

                trans.Commit();

 

                pmtEntOpts = new PromptEntityOptions

     ("\nSelect AutoCad entity to be converted : ");

                pmtEntRes = ed.GetEntity(pmtEntOpts);

                if (pmtEntRes.Status ==

                                    PromptStatus.OK)

                {

 

                    ObjectId oidEntityId =

                                 pmtEntRes.ObjectId;

                    // Add the command to the ResBuf

                    rb.Add(new TypedValue

                 (5005, "_PlantPipeSupportConvert"));

 

                    // Add the selected

                    // entity ObjectId

                    rb.Add(new TypedValue

                                (5006, oidEntityId));

                    // return on the command line

                    rb.Add(new TypedValue(5005, ""));

 

                    // mid point of the selected pipe

                    rb.Add(new TypedValue

                   (5009, p3dSupportInsertionPoint));

 

                    acedCmd(rb.UnmanagedObject);

 

                }

            }

        }

        catch

        {

            if (trans != null)

            {

                trans.Abort();

                trans.Dispose();

            }

        }

    }

}

Use LayerFilterTree to add a new Layer Filter

By Wayne Brill

Here is a C# example that creates a new layer filter. If a layer filter named "MyFilter" already exists, the code makes it the active Layer Filter instead of creating a new one.

[CommandMethod("addFilt")]

public void addLayerFilter()

{

    Editor ed = Application.DocumentManager.

                    MdiActiveDocument.Editor;

 

    try

    {

        // Access tree of layer filters.

        LayerFilterTree lyrTree =

            HostApplicationServices.

                 WorkingDatabase.LayerFilters;

 

        int fltCount = lyrTree.Root.

                          NestedFilters.Count;

 

        for (int i = 0; i <= fltCount - 1; i++)

        {

            LayerFilter lyrFilt = lyrTree.Root.

                               NestedFilters[i];

            if (lyrFilt.Name == "MyFilter")

            {

                ed.WriteMessage

("\nMyFilter already exists, making it current");

                // This is the way I found to

                // make a Layer Filter current

                //use LayerFilterTree constructor

                LayerFilterTree lyrTree2 =

                     new LayerFilterTree

                           (lyrTree.Root, lyrFilt);

                HostApplicationServices.

                    WorkingDatabase.LayerFilters =

                                          lyrTree2;

                return;

 

            }

        }

 

        // If we get here then Layer

        // Filter named MyFilter does not exist

        // create it

        LayerFilter lyrFilt2 = new LayerFilter();

        lyrFilt2 = new LayerFilter();

        lyrFilt2.Name = "MyFilter";

        lyrFilt2.FilterExpression =

                            "NAME==\"WBLayer*\"";

        // Add the Layer Filter to the

        // NestedFilters of the LayerFilters

        lyrTree.Root.NestedFilters.Add(lyrFilt2);

        // Use the constructor to make the Layer

        // Filter current

        // and update the Layer Palette. Without

        // this you can run the

        // LAYER command and see the new

        // layer filter

        lyrTree = new LayerFilterTree

                         (lyrTree.Root, lyrFilt2);

        HostApplicationServices.WorkingDatabase.

                           LayerFilters = lyrTree;

    }

    catch (System.Exception ex)

    {

        // Do something here

        ed.WriteMessage("Oops!" + ex.ToString());

    }

}

Use the Name property of the RibbonTabSource to Identify a WSRibbonTabSourceReference in the WorkspaceRibbonTab Collection

By Wayne Brill

If you need to remove an existing tab from workspace tabs using the name of the tab, you can iterate the RibbonTabSource elements and get the ElementID from the RibbonTabSource. (The RibbonTabSource class has a name property) The ElementID will be the TabId of the WSRibbonTabSourceReference. Below is the pertinent code from the AutoCAD 2013 C# project. (_TestFindWithRibbonTab) The command "DELTAB" finds the Home 2D Tab and removes it from a workspace.

Download _Test_FindWithRibbonTab

Note: Keep in mind that it could be possible that there is more than one RibbonTabSource with the same name. (ElementID and TabId are unique in a menu group however)

[CommandMethod("DELTAB")]

public void delTab()

{

 

    WSRibbonRoot wrkSpaceRibbonRoot = null;

    WorkspaceRibbonTabCollection

              wsRibbonTabCollection = null;

 

    Editor ed =

        Autodesk.AutoCAD.ApplicationServices.

                 Application.DocumentManager.

                    MdiActiveDocument.Editor;

 

    try

    {

        WorkspaceCollection WsCollect =

                                cs.Workspaces;

        if ((WsCollect.Count <= 0))

        {

            ed.WriteMessage

    ("Failed to Get the WorkspaceCollection\n");

            return;

        }

 

        string strWrkSpaceName = "Acme Workspace";

 

        // If the workspace doesnot exist

        if (-1 == cs.Workspaces.

            IndexOfWorkspaceName(strWrkSpaceName))

        {

            // Create the workspace

            Workspace nwWs = new Workspace

                            (cs, strWrkSpaceName);

            wrkSpaceRibbonRoot =

                         nwWs.WorkspaceRibbonRoot;

        }

        else

        {

            for (int i = 0; i < WsCollect.Count; i++)

            {

                // If name of workspace is

                // "Acme Workspace" then get

                // the WSRibbonRoot

                if (WsCollect[i].Name ==

                                     strWrkSpaceName)

                {

                   wrkSpaceRibbonRoot =

                    WsCollect[i].WorkspaceRibbonRoot;

                   break;

                }

            }

        }

        //Get the Tabcollection in the

        // Acme Workspace

        wsRibbonTabCollection =

                   wrkSpaceRibbonRoot.WorkspaceTabs;

        if (wsRibbonTabCollection.Count <= 0)

        {

            ed.WriteMessage

     ("Acme Workspace does not contain any Tabs\n");

            return;

        }

 

        RibbonRoot ribbonRoot =

                      cs.MenuGroup.RibbonRoot;

        RibbonTabSourceCollection tabs = null;

        tabs = ribbonRoot.RibbonTabSources;

        // Change this to the name of the

        // tab to be removed

        string strRibTabSrcName = "Home - 2D";

        string strRibTabSrcTabId = null;

 

        foreach (RibbonTabSource ribTabSrc in tabs)

        {

 

            if (ribTabSrc.Name != null)

            {

                if (ribTabSrc.Name.ToString() ==

                                   strRibTabSrcName)

                {

                    strRibTabSrcTabId =

                     ribTabSrc.ElementID.ToString();

                    break;

                }

            }

        }

 

        foreach (WSRibbonTabSourceReference wsTabRef

                             in wsRibbonTabCollection)

        {

            if (wsTabRef.TabId.ToString() ==

                                   strRibTabSrcTabId)

            {

                wsRibbonTabCollection.Remove

                                          (wsTabRef);

                break;

            }

        }

        saveCui();

    }

    catch (System.Exception ex)

    {

        ed.WriteMessage(ex.ToString());

    }

}

 

Note: If you are debugging the ribbon may be not shown the next time you start AutoCAD. (Run the RIBBON command).

Use getClosestPointTo() and onSegAt() to locate a polyline vertex near a point

By Wayne Brill

You can use getClosestPointTo() and onSegAt() to find a vertex of a polyline closest to a selected point. Here is an ObjectARX example that shows this idea. To try this run a command that runs this function. If you select a polyline the command line will display the number of the segment of the polyline (where you selected the polyline).

 static void TEST_PointOnPoly(void)

{

 

  ads_name ename;

  ads_point pt, ptWcs;

  AcDbObjectId Id;

 

  if(acedEntSel(_T("Select Pline: "),

                      ename,pt)!=RTNORM)

   return;

 

  // Convert to WCS incase selection was made

  // while in a UCS.

  acdbUcs2Wcs(pt, ptWcs, Adesk::kFalse);

  acdbGetObjectId(Id,ename);

  AcDbEntity* pEnt;

  acdbOpenObject(pEnt,Id,AcDb::kForRead,false);

 

  AcDbPolyline* pLine=NULL;

  pLine=AcDbPolyline::cast(pEnt);

 

  if(!pLine)

  {

   acutPrintf(_T

    ("Selected Entity not a Polyline"));

   pEnt->close();

   return;

  }

 

  AcGePoint3d clickpt;

  // This will convert the pick point to a

  // point on the polyline

  pLine->getClosestPointTo(asPnt3d(ptWcs), clickpt);

  // Convert to 2d point, needed below...

  AcGePoint2d clickpt2d(clickpt.x, clickpt.y);

 

  for(unsigned int c=0; pLine->numVerts() > c ; c++)

  {

   double segParam;

   // This is the test filter here...it uses the

   // nifty API onSegAt

   if(pLine->onSegAt(c, clickpt2d, segParam)) 

   {

    acutPrintf(_T("Selected Segment: %d \n"),c+1);

    break;

   }

  }

  pLine->close();

}

DCL dialog that displays slides not showing slides if path contains parenthesis

By Wayne Brill

Issue

I have  a DCL dialog that has slides. The slides are not being displayed. I use the "VSLIDE" command and select a sld and I get  an AutoCAD Message that states "Program Files.slb" "Can't find file in search path". How can I get the slides to display? 

Solution

If the directory that contains a SLB file contains parenthesis, such as "Program Files (x86)\", the slides will not display. The DCL call into the slide library is being confused. It uses the parenthesis as a pointer into the library.

The solution is to modify the AutoLISP code not to use the path and move the slide library into support search path that does not contain parenthesis.

Turn off the Automatic Save of dsd files when running the Publish command

By Wayne Brill

Issue

I have developed an application for one of my clients that uses the PUBLISH command.  Every time I publish drawings I get error messages related to DSD files. How can I stop AutoCAD from saving DSD files automatically?

Solution

There is a setting in Options that will display the dialog that will ask if you want to save the dsd file. To change this do the following: Run the Options command and go to the System Tab. Click the Hidden Messages setting button. There will be a Publish – Save Sheet List  checkbox.  Check it and click Ok all the way out of options.

When you publish you should be prompted to save the current list of sheets. Click “Always perform my current choice” and select No.

Use SelectCrossingPolygon to select entities in view other than plan

By Wayne Brill

Issue

I am using Editor SelectCrossingWindow to select Entities. If the view is not a plan view then some of the entities inside of the window defined by the points are not included in the selection.

Solution

The selection area using SelectCrossingWindow() is going to be a rectangular shape in WCS that is horizontal. To see the selection area for the crossing window, in WCS (plan view) draw a rectangle using the REC command using the points used for the crossing window. Then go to the non plan view, change the UCS to view and draw another rectangle by snapping to the points used for the first rectangle. Change the UCS back to world before you run the code and you will see the entities that are inside or cross the second rectangle are selected.

Instead of using SelectCrossingWindow use SelectCrossingPolygon(). Here is an example. If the entities are visible, then this will get the entities in the area defined by the points. (Regardless of the current view). This example uses a filter to only select lines.

CommandMethod("SEL")]

public void MySelection()

{

    Document doc = Autodesk.AutoCAD

        .ApplicationServices.Application

        .DocumentManager.MdiActiveDocument;

    Editor ed = doc.Editor;

 

    Point3d p1 = new Point3d(10.0, 10.0, 0.0);

    Point3d p2 = new Point3d(10.0, 11.0, 0.0);

    Point3d p3 = new Point3d(11.0, 11.0, 0.0);

    Point3d p4 = new Point3d(11.0, 10.0, 0.0);

 

    Point3dCollection pntCol =

                      new Point3dCollection();

    pntCol.Add(p1);

    pntCol.Add(p2);

    pntCol.Add(p3);

    pntCol.Add(p4);

 

    int numOfEntsFound = 0;

 

    PromptSelectionResult pmtSelRes = null;

 

    TypedValue[] typedVal = new TypedValue[1];

    typedVal[0] = new TypedValue

                 ((int)DxfCode.Start, "Line");

 

    SelectionFilter selFilter =

              new SelectionFilter(typedVal);

    pmtSelRes = ed.SelectCrossingPolygon

                         (pntCol, selFilter);

    // May not find entities in the UCS area

    // between p1 and p3 if not PLAN view

    // pmtSelRes =

    //    ed.SelectCrossingWindow(p1, p3, selFilter);

 

    if (pmtSelRes.Status == PromptStatus.OK)

    {

        foreach (ObjectId objId in

            pmtSelRes.Value.GetObjectIds())

        {

            numOfEntsFound++;

        }

        ed.WriteMessage("Entities found " +

                    numOfEntsFound.ToString());

    }

    else

        ed.WriteMessage("\nDid not find entities");

}

Return nil to indicate an error condition in a .NET LispFunction

By Wayne Brill

Issue

I am implementing functionality in .NET that I am using from AutoLISP. How can I return an error condition from the .NET function?

Solution

One suggestion is to return nil from the .NET function using the LispDataType. If the function does return nil you could then handle that appropriately. (Or you could return an integer and respond to that value in the LISP function)

Here is an excerpt from the AutoCAD .NET Managed Class Reference guide for the LispDataType:

Public Enum LispDataType
  Angle = &H138c
  DottedPair = &H139a
  Double = &H1389
  Int16 = &H138b
  Int32 = &H1392
  ListBegin = &H1398
  ListEnd = &H1399
  Nil = &H139b
  None = &H1388
  ObjectId = &H138e
  Orientation = &H1390
  Point2d = &H138a
  Point3d = &H1391
  SelectionSet = &H138f
  T_atom = &H139d
  Text = &H138d
  Void = &H1396
End Enum

Here is a VB example. Notice that if the entity is not selected ok, the routine returns nil.

<LispFunction("getId")>

Public Function test _

  (ByVal myLispArgs As ResultBuffer) As ResultBuffer

    ' This example asks the user to select

    ' an(entity) The object id of the entity is

    ' returned to the calling lisp function

    Dim rbfResult As ResultBuffer

    Dim ed As Autodesk.AutoCAD.EditorInput.Editor

    ed = Autodesk.AutoCAD.ApplicationServices. _

                  Application.DocumentManager. _

                        MdiActiveDocument.Editor

 

    Dim prmptEntOpts As New PromptEntityOptions _

                                  ("Select Entity")

    Dim prmptEntRes As PromptEntityResult

 

    ' Get the entity from the users selection

    prmptEntRes = ed.GetEntity(prmptEntOpts)

 

    ' Make sure the entity was selected ok

    If prmptEntRes.Status <> PromptStatus.OK Then

        rbfResult = New ResultBuffer _

              (New TypedValue(LispDataType.Nil))

        Return rbfResult

    End If

 

    ' Return the ObjectId to the Lisp function

    Dim objId As ObjectId

    objId = prmptEntRes.ObjectId

    rbfResult = New ResultBuffer _

      (New TypedValue(LispDataType.ObjectId, objId))

 

    Return rbfResult

 

End Function

Here is a LISP function that uses the .NET function:

    (defun c:testID ( / objId nilTest ent)
    (setq objId (getId))
    (setq nilTest (nth 0 objId))
    (if (= nilTest nil)
        (princ "Entity not selected")
      )
 
     (if (/= nilTest nil)
     (progn
          (vl-load-com);ensure COM API is available
        (setq ent (vlax-ename->vla-object (nth 0 objId)));the 0 element is an ename
      (vla-highlight ent :vlax-true); highlight the entity using COM call
     );progn
    );if
    (princ)
    )