Private Sub SetEnterHandlerForAll(ByVal ListofControls As _
  Control.ControlCollection)
    for each ctrl as Control in ListofControls
        if( TypeOf( ctrl ) is TextBox Then
            AddHandler ctrl.Enter, AddressOf AllEnter
        end if
        if ctrl.Controls.Count > 0 then
            SetEnterHandlerForAll(ctrl.Controls)
        end if
    next
End Sub