Vertices or Grip Points of MULTILEADER

[subash.nalla]

Hi Team, I have to get the vertices or Grip points of a MULTILEADER and looking for C# code for that.

[norman.yuan]

Have you looked into/tried with MLeader.GetVertex(int, int) ? You may also need to look into MLeader.GetFirst[Last]Vertex(int).

[subash.nalla]

Hi Norman. I have tried both options but getting the attached exception (Exception.PNG). Can you please suggest me what I am doing wrong here.

This is my code, please let me know for any other information.

Entity ent = tr.GetObject(selObj.ObjectId, OpenMode.ForRead) as Entity;
MLeader mLeader = ent as MLeader;

Point3d pntFirst = mLeader.GetVertex(0, 0);  or Point3d pntFirst = mLeader.GetFirstVertex(0);

I am getting same exception for when tried using both options.

[norman.yuan · Accepted solution]

Well, following code works for me with a simple MLeader entity as shown in picture below: 

        [CommandMethod("MLTest")]
        public static void TestMLeader()
        {
            var dwg = CadApp.DocumentManager.MdiActiveDocument;
            var ed = dwg.Editor;

            var res = ed.GetEntity("\nSelect an MLEADER entity:");
            if (res.Status == PromptStatus.OK)
            {
                using (var tran = dwg.TransactionManager.StartTransaction())
                {
                    var mleader = (MLeader)tran.GetObject(res.ObjectId, OpenMode.ForRead);

                    var leaderIndex = (int)mleader.GetLeaderIndexes()[0];

                    var leaderlineIndexes = mleader.GetLeaderLineIndexes(leaderIndex);
                    var leaderlineIndex = (int)leaderlineIndexes[0];

                    var firstVertex = mleader.GetFirstVertex(leaderlineIndex);
                    var lastVertex = mleader.GetLastVertex(leaderlineIndex);

                    ed.WriteMessage(
                        $"\nFirst vertex = {firstVertex.ToString()}");
                    ed.WriteMessage(
                        $"\nLast vertex = {lastVertex.ToString()}");

                    var vertex = mleader.GetVertex(leaderlineIndex, 0);
                    ed.WriteMessage(
                        $"\nFirst vertex of the first leader line = {vertex.ToString()}");

                    tran.Commit();
                }
            }
        }

Basically, you need to call GetLeaderIndexes() and GetLeaderLineIndexes() to see if there is how many leaders and how many leader lines. there could be leader only (i.e. a leader without leader line). Since you need to get vertex on LEADERLINE, there must be at least one LeaderLine for your code to work.

[subash.nalla]

Hi Norman, thanks for the code sample and looks like I am able to get the vertices now and only thing missing in my code was 

var leaderlineIndex = (int)leaderlineIndexes[0];

I was passing leaderlineIndexes to find the first or last vertex.