Unmerging cells in an AutoCAD table using .NET

A question came in, last week, via a comment on this post. Daniel wanted to unmerge the title cells of a table:

Very nice tutorial. based on this I manange to create the VB. NET code for my table style, but I face with a problem that I could not change the Title to be unmerged.
In this moment, as default, it is merged and I want it to have it not merged.
What is code for this ? I tried to find it out by

ts.SetCellClass(RowType.TitleRow, MergeCellStyleOption.None

but is not working. i get error on:

sd.UpgradeOpen() line

I took a quick look at the Table class and found that this C# code did the job:

using Autodesk.AutoCAD.ApplicationServices;

using Autodesk.AutoCAD.DatabaseServices;

using Autodesk.AutoCAD.EditorInput;

using Autodesk.AutoCAD.Runtime;

 

namespace TableStyleEditing

{

  public class Commands

  {

    [CommandMethod("UTT")]

    public void UnmergeTableTitle()

    {

      var doc = Application.DocumentManager.MdiActiveDocument;

      if (doc == null) return;

      var ed = doc.Editor;

 

      // Select a table

 

      var peo = new PromptEntityOptions("\nSelect table");

      peo.SetRejectMessage("\nMust be a table.");

      peo.AddAllowedClass(typeof(Table), false);

      var per = ed.GetEntity(peo);

      if (per.Status != PromptStatus.OK)

        return;

 

      using (var tr = doc.TransactionManager.StartTransaction())

      {

        var table = tr.GetObject(per.ObjectId, OpenMode.ForWrite) as Table;

        if (table != null)

        {

          // Get the first row

 

          var row = table.Rows[0];

 

          // If it is merged, unmerge it

 

          if (row.IsMerged.HasValue && row.IsMerged.Value)

          {

            table.UnmergeCells(row);

            ed.WriteMessage("\nUnmerged first row.");

          }

          else

          {

            ed.WriteMessage("\nFirst row is not merged.");

          }

        }

        tr.Commit();

      }

    }

  }

}

 

Here’s what happens when you run the UTT command and select a table with a merged title row:

The UTT command is currently hardcoded to unmerge the first row in the selected table, but it could of course be generalised to work on any range of merged cells.