Imports Autodesk.AutoCAD.Runtime

Imports Autodesk.AutoCAD.ApplicationServices

Imports Autodesk.AutoCAD.DatabaseServices

Imports Autodesk.AutoCAD.Geometry

<CommandMethod("AddCircle")> _

Public Sub AddCircle()

  '' Get the current document and database

  Dim acDoc As Document = Application.DocumentManager.MdiActiveDocument

  Dim acCurDb As Database = acDoc.Database

  '' Start a transaction

  Using acTrans As Transaction = acCurDb.TransactionManager.StartTransaction()

      '' Open the Block table for read

      Dim acBlkTbl As BlockTable

      acBlkTbl = acTrans.GetObject(acCurDb.BlockTableId, OpenMode.ForRead)

      '' Open the Block table record Model space for write

      Dim acBlkTblRec As BlockTableRecord

      acBlkTblRec = acTrans.GetObject(acBlkTbl(BlockTableRecord.ModelSpace), _

                                      OpenMode.ForWrite)

      '' Create a circle that is at 2,3 with a radius of 4.25

      Dim acCirc As Circle = New Circle()

      acCirc.Center = New Point3d(2, 3, 0)

      acCirc.Radius = 4.25

      '' Add the new object to the block table record and the transaction

      acBlkTblRec.AppendEntity(acCirc)

      acTrans.AddNewlyCreatedDBObject(acCirc, True)

      '' Save the new object to the database

      acTrans.Commit()

  End Using

End Sub

using Autodesk.AutoCAD.Runtime;

using Autodesk.AutoCAD.ApplicationServices;

using Autodesk.AutoCAD.DatabaseServices;

using Autodesk.AutoCAD.Geometry;

[CommandMethod("AddCircle")]

public static void AddCircle()

{

  // Get the current document and database

  Document acDoc = Application.DocumentManager.MdiActiveDocument;

  Database acCurDb = acDoc.Database;

  // Start a transaction

  using (Transaction acTrans = acCurDb.TransactionManager.StartTransaction())

  {

      // Open the Block table for read

      BlockTable acBlkTbl;

      acBlkTbl = acTrans.GetObject(acCurDb.BlockTableId,

                                   OpenMode.ForRead) as BlockTable;

      // Open the Block table record Model space for write

      BlockTableRecord acBlkTblRec;

      acBlkTblRec = acTrans.GetObject(acBlkTbl[BlockTableRecord.ModelSpace],

                                      OpenMode.ForWrite) as BlockTableRecord;

      // Create a circle that is at 2,3 with a radius of 4.25

      Circle acCirc = new Circle();

      acCirc.Center = new Point3d(2, 3, 0);

      acCirc.Radius = 4.25;

      // Add the new object to the block table record and the transaction

      acBlkTblRec.AppendEntity(acCirc);

      acTrans.AddNewlyCreatedDBObject(acCirc, true);

      // Save the new object to the database

      acTrans.Commit();

  }

}