Visual Basic.NET - boton para ejecutar comando creado en VB.NET

<CommandMethod("abredibujo", CommandFlags.Session)>

Public Sub OpenDrawing()

    Dim strFileName As String = "C:\Rectangulo.dwg"

    Dim acDocMgr As DocumentCollection = Application.DocumentManager

    If (IO.File.Exists(strFileName)) Then

        DocumentCollectionExtension.Open(acDocMgr, strFileName, False)

    Else

        acDocMgr.MdiActiveDocument.Editor.WriteMessage("File " & strFileName & " does not exist.")

    End If

End Sub

Public Class Class1

    <CommandMethod("Insertabloque")>

    Public Sub InsertingABlock()

        ' Get the current database and start a transaction

        Dim acCurDb As Autodesk.AutoCAD.DatabaseServices.Database

        acCurDb = Application.DocumentManager.MdiActiveDocument.Database

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

            ' Open the Block table for read

            Dim acBlkTbl As BlockTable

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

            Dim blkRecId As ObjectId = ObjectId.Null

            If Not acBlkTbl.Has("CircleBlock") Then

                Using acBlkTblRec As New BlockTableRecord

                    acBlkTblRec.Name = "CircleBlock"

                    ' Set the insertion point for the block

                    acBlkTblRec.Origin = New Point3d(0, 0, 0)

                    ' Add a circle to the block

                    Using acCirc As New Circle

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

                        acCirc.Radius = 2

                        acBlkTblRec.AppendEntity(acCirc)

                        acBlkTbl.UpgradeOpen()

                        acBlkTbl.Add(acBlkTblRec)

                        acTrans.AddNewlyCreatedDBObject(acBlkTblRec, True)

                    End Using

                    blkRecId = acBlkTblRec.Id

                End Using

            Else

                blkRecId = acBlkTbl("CircleBlock")

            End If

            ' Insert the block into the current space

            If blkRecId <> ObjectId.Null Then

                Using acBlkRef As New BlockReference(New Point3d(0, 0, 0), blkRecId)

                    Dim acCurSpaceBlkTblRec As BlockTableRecord

                    acCurSpaceBlkTblRec = acTrans.GetObject(acCurDb.CurrentSpaceId, OpenMode.ForWrite)

                    acCurSpaceBlkTblRec.AppendEntity(acBlkRef)

                    acTrans.AddNewlyCreatedDBObject(acBlkRef, True)

                End Using

            End If

            ' Save the new object to the database

            acTrans.Commit()

            ' Dispose of the transaction

        End Using

    End Sub

End Class

Public Class Form1

    Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click

        AddHandler Button1.Click, AddressOf InsertingABlock()

    End Sub

End Class

Public Class Form1

    Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click

        Dim clase1 As New Class1

        clase1.InsertingABlock()

    End Sub

End class