Yes, it's possible. You need to add references to EnvDTE and
Microsoft.Office.Core. Below is the code (VB.NET).

Carlos J. Quintero

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Private m_objDTE As EnvDTE.DTE
Private WithEvents m_objCommandBarButton As
Microsoft.Office.Core.CommandBarButton

Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs)
Handles MyBase.Load

 Dim objType As Type
 Dim objCommandBar As Microsoft.Office.Core.CommandBar
 Dim objCommandBarControl As Microsoft.Office.Core.CommandBarControl

 Try

  objType = System.Type.GetTypeFromProgID("VisualStudio.DTE")
  m_objDTE = DirectCast(System.Activator.CreateInstance(objType),
EnvDTE.DTE)
  m_objDTE.MainWindow.Visible = True
  objCommandBar = m_objDTE.CommandBars.Item("Tools")
  objCommandBarControl =
objCommandBar.Controls.Add(Microsoft.Office.Core.MsoControlType.msoControlButton)
  m_objCommandBarButton = DirectCast(objCommandBarControl,
Microsoft.Office.Core.CommandBarButton)

  m_objCommandBarButton.Caption = "Test"

 Catch ex As Exception
  MessageBox.Show(ex.ToString)
 End Try

End Sub

Private Sub Form1_Closed(ByVal sender As Object, ByVal e As
System.EventArgs) Handles MyBase.Closed

 Try

  If Not (m_objCommandBarButton Is Nothing) Then
   m_objCommandBarButton.Delete()
  End If

  If Not (m_objDTE Is Nothing) Then
   m_objDTE.Quit()
  End If

 Catch ex As Exception
  MessageBox.Show(ex.ToString)
 End Try

End Sub

Private Sub m_objCommandBarButton_Click(ByVal Ctrl As
Microsoft.Office.Core.CommandBarButton, ByRef CancelDefault As Boolean)
Handles m_objCommandBarButton.Click

 MessageBox.Show("You clicked me!")

End Sub