you can take the idea to add the code, to your class.


Dim intLastIndex As Integer

Private Sub ComboBox1_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ComboBox1.SelectedIndexChanged
If Not AllowChangeIndex() Then
CType(sender, ComboBox).SelectedIndex = intLastIndex
End If

intLastIndex = CType(sender, ComboBox).SelectedIndex
End Sub

'You could also use a variable as a flag that indicates
'if the user can or not change the item
Private Function AllowChangeIndex() As Boolean
'Code to allow or not change the index
Return False
End Function