C# DataGridView and Windows Form

Question

I'm writing AutoCAD 2013 .NET plug-in with Windows Form, using C#. When I using modeless form in the command

Autodesk.AutoCAD.ApplicationServices.Application.ShowModelessDialog (new Form1 ());

instead of next code

System.Windows.Forms.Application.EnableVisualStyles ();
// System.Windows.Forms.Application.SetCompatibleTextRenderingDefault(false); // here I get exception too
System.Windows.Forms.Application.Run (new Form1 ());

I have lock_exception in the line

BlockTableRecord btrRecord = new BlockTableRecord ();
btTable.UpgradeOpen (); // <--- here Exception

Thank you, in advance.

Answer 1

The right answer is

To make some actions with model of autocad, when modeless dialog is opened, it is nessesary to lock active document, that can't be modified other way, while actions is performed. For example:

  public void CreateBlockReference (string strBlockName, Point3d Origin)
  {
   // First: lock document by next instruction
   DocumentLock dl = Application.DocumentManager.MdiActiveDocument.LockDocument ();
   // Second: create separate transaction for each your action
   Transaction   t = db.TransactionManager.StartTransaction ();

   try
   {
    // Third: try to make the action your wish

    // here I'm getting the table of Blocks this drawing.dwg
    BlockTable btTable = (BlockTable)t.GetObject (db.BlockTableId, OpenMode.ForRead);

    // now get the space of AutoCAD model
    BlockTableRecord btrModelSpace = (BlockTableRecord)t.GetObject (
                              btTable[BlockTableRecord.ModelSpace], OpenMode.ForWrite);

    if( !btTable.Has (strBlockName) )
    {
     ed.WriteMessage     (string.Format (msgs.BlockNoExist, strBlockName));
     throw new Exception (ErrorStatus.MissingBlockName,
                          string.Format (msgs.BlockNoExist, strBlockName));
    }
    // extract the Block definition, that I want to create a reference
    ObjectId myBlockId = btTable[strBlockName];

    // next I'm creating the new instance of my Block by definition
    BlockReference brRefBlock = new BlockReference (Origin, myBlockId);

    // insert created blockreference into space of model 
    btrModelSpace.AppendEntity (brRefBlock);
    t.AddNewlyCreatedDBObject (brRefBlock, true);

    // successfully close transaction
    t.Commit ();
   } // end try
   finally // or not
   { t.Dispose ();
    dl.Dispose (); // END OF LOCKING!!! ANYWAY
   } // end finally
  }