Topic: A debugging exercise ...

[Kerry]

This is a programming exercise ... not optimised and not bomb proof.
.. and needs to have UCS translations added

I wanted to write a generic getObject Method to add to my Library
.. and also had a play with Debug.WriteLine(.. to the Output screen in VS2008

The core functional problem (from another forum) was
" to select a Line and Move its Endpoint"

Here's a Video ..




More to follow.

[Kerry]

This is the Output Pane and Locals Pane at the completion of the routine.
Note the Breakpoint at the last brace of the transaction statement.

T write the data to the output Pane ;

add a using statement
using System.Diagnostics;

then use the WriteLine Method of the Debug Class ;

            Debug.WriteLine("\nSelectLine_1 : -------------------------------");
            Debug.WriteLine("\nEntity.GetType() : " + pickedLine.GetType().Name);

etc

[Kerry]

Then the Code

.. and a file attachment for members ..

Comments, Improvements, ideas appreciated ..

Code: [Select]

//CodeHimBelongaKdub ©  May2009

    public class MoveEndOfLine
    {
        ///-------------------------------------------------------------------
        ///
        [CommandMethod("SOL")]
        public void SelectLine_1()
        {
            Database db = HostApplicationServices.WorkingDatabase;
            Editor ed = AcadApp.DocumentManager.MdiActiveDocument.Editor;

            Point3d pickPoint;
            ObjectId pickedID = SelectObject(
                "\nSelect Line entity near end to Relocate : ",
                typeof(Line), out pickPoint
            );

            if (pickedID.IsNull)
            {
                WinForms.MessageBox.Show(
                    "ooops !! \nCancelling Routine.",  "F.U.B.B.",
                    WinForms.MessageBoxButtons.OK,
                    WinForms.MessageBoxIcon.Hand
                );
                return;
            }
            Line pickedLine;
            using (Transaction tr = db.TransactionManager.StartTransaction())
            {
                pickedLine = tr.GetObject(pickedID, OpenMode.ForRead) as Line;
            }
            Debug.WriteLine("\nSelectLine_1 : -------------------------------");
            Debug.WriteLine("\nEntity.GetType() : " + pickedLine.GetType().Name);
            Debug.WriteLine("\npickedPoint() : " + pickPoint);
            Debug.WriteLine("\nstartPoint() : " + pickedLine.StartPoint);
            Debug.WriteLine("\nendPoint() : " + pickedLine.EndPoint);

            Point3d vertexPoint;
            Point3d basePoint;
            bool startPoint_IS_vertex = (
                pickPoint.DistanceTo(pickedLine.StartPoint)
                <= 
                pickPoint.DistanceTo(pickedLine.EndPoint)
            );
            if (startPoint_IS_vertex)
            {
                Debug.WriteLine("\nStartPoint to PickPoint : "
                    + pickPoint.DistanceTo(pickedLine.StartPoint));
                vertexPoint = pickedLine.StartPoint;
                basePoint = pickedLine.EndPoint;               
            }
            else
            {
                Debug.WriteLine("\nEndPoint to PickPoint : "
                    + pickPoint.DistanceTo(pickedLine.EndPoint));
                vertexPoint = pickedLine.EndPoint;
                basePoint = pickedLine.StartPoint;
            }
            //-----------------------------------------------------------------
           
            PromptPointOptions ppo = new PromptPointOptions("\nGet New EndPoint: ");
            ppo.UseBasePoint = true;
            ppo.UseDashedLine = true;
            ppo.BasePoint = basePoint;

            PromptPointResult ppr = ed.GetPoint(ppo);
            if (ppr.Status != PromptStatus.OK)
            {
                ed.WriteMessage("\nSelection is null ... Cancelling Routine.");
                return;               
            }
            Point3d p = ppr.Value;

            Debug.WriteLine("\nNew Vertex Location : " + p);
           
            // Change property of appropriate Line End to be the selected Point.
            using (Transaction tr = db.TransactionManager.StartTransaction())
            {
                pickedLine = tr.GetObject(pickedID, OpenMode.ForWrite) as Line;
                if (startPoint_IS_vertex)
                {
                    pickedLine.StartPoint = p;
                }
                else
                {
                    pickedLine.EndPoint = p;
                }
                tr.Commit();
               
            }
 
        }


Code: [Select]

//CodeHimBelongaKdub ©  May2009

        static ObjectId SelectObject(string prompt,
            System.Type objectClass,
            out Point3d pickPoint)
        {
            Editor ed = AcadApp.DocumentManager.MdiActiveDocument.Editor;
            using (Transaction tr = ed.Document.Database.TransactionManager.StartTransaction())
            {
                while (true)
                {
                    PromptEntityResult res = ed.GetEntity(prompt);
                    if (res.Status != PromptStatus.OK)
                        return ObjectId.Null;
                    DBObject dbObj = tr.GetObject(res.ObjectId, OpenMode.ForRead);
                    if (objectClass.IsAssignableFrom(dbObj.GetType()))
                    {
                        pickPoint = res.PickedPoint;
                        return res.ObjectId;
                    }
                    ed.WriteMessage("\nInvalid selection, {0} entity expected",
                        RXClass.GetClass(objectClass).DxfName);
                }
            }
        }


[Glenn R]

Kerry,

What's your reasoning behind using IsAssignableFrom() ?

Cheers,
Glenn.

[Kerry]

Hi Glenn

I stole that idea from Tony

.. lets me do this,

Code: [Select]

        ///----------------------------------------------------------
        ///
        [CommandMethod("S1")]
        public static void Select_Curved_Thingy()
        {
            Database db = HostApplicationServices.WorkingDatabase;
            Editor ed = AcadApp.DocumentManager.MdiActiveDocument.Editor;

            Point3d pickPoint;
            ObjectId pickedID = SelectObject(
                "\nSelect Curved Thingy : ",
                typeof(Curve), out pickPoint
            );           
            if (pickedID.IsNull)
            {               
                return;
            }
            Curve PickedThingy;
            using (Transaction tr = db.TransactionManager.StartTransaction())
            {
                PickedThingy = tr.GetObject(pickedID, OpenMode.ForRead) as Curve;
            }
            ed.WriteMessage("\nSelectLine_1 : -------------------------------");
            ed.WriteMessage("\nGetType() : " + PickedThingy.GetType().Name);
            ed.WriteMessage("\npickedPoint() : " + pickPoint);
        }
        ///----------------------------------------------------------
        ///

which selects anything derived from the defined class

[Glenn R]

OK, thanks for that Kerry. I would have used PromptEntityOptions.AddAllowedClass(...), so I was just curious as to the reasoning.

[Kerry]

Glenn,
yes, that's probably more intuitive, and equally effective at first testing

Code: [Select]


        ///----------------------------------------------------------
        ///
        //CodeHimBelongaKdub ©  May2009
        static ObjectId SelectObject(string prompt, System.Type objectClass, out Point3d pickPoint)
        {
            Editor ed = AcadApp.DocumentManager.MdiActiveDocument.Editor;
            using (Transaction tr = ed.Document.Database.TransactionManager.StartTransaction())
            {
                PromptEntityOptions peo = new PromptEntityOptions(prompt);               
                peo.SetRejectMessage("\nInvalid selection, "
                    + objectClass.Name
                    + " entity expected");
                peo.AddAllowedClass(objectClass, false);

                PromptEntityResult res = ed.GetEntity(peo);
                if (res.Status != PromptStatus.OK)
                {
                    ed.WriteMessage("\nNothing Selected");
                    return ObjectId.Null;
                }
                // else all is good :)
                DBObject dbObj = tr.GetObject(res.ObjectId, OpenMode.ForRead);
                pickPoint = res.PickedPoint;
                return res.ObjectId;
            }
        }
       

        ///----------------------------------------------------------
        ///


[Glenn R]

Thought you might like it

Kerry, what IDE enhancement(s) are you running? ie. your piccy shows vertical lines connecting braces, lines defining the scope of 'if' blocks etc.

[Kerry]

Glenn,

That would be CodeRush and Refactor from devexpress
.. actually the light free version
http://www.devexpress.com/Products/Visual_Studio_Add-in/CodeRushX/

Was running WholeTomato Visual AssistX .. but took it off rather than upgrade.

regards
kdub

[Glenn R]

I suspected it was either of those 2 - thanks for the confirmation.

Cheers,
Glenn.

[Kerry]

just to bring things up to date ..
.. and to further show how badly I translate Chinese
The original poster wasn't trying to move the endpoint
he was trying to control the DrawOrder of objects  

Bill Wu from AutoDesk China posted something on his blog late last year
http://www.cnblogs.com/wf225/archive/2008/11/14/1333852.html

// // Get the DrawOrderTable
    //DrawOrderTable orderTable = tr.GetObject(btr.DrawOrderTableId, OpenMode.ForWrite) as DrawOrderTable;
  // < .. big snip ..>
   // orderTable.MoveAbove(ids, id2); //It's OK.
   // orderTable.MoveBelow(ids, id2); //It's OK.
   // orderTable.MoveToBottom(ids); //It's OK.
   // orderTable.MoveToTop(ids); //It's OK.


The blog is well worth a look.

... and of course, Kean has a few references on his Blog