Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As _
      System.EventArgs) Handles Button1.Click
        Me.getControl("TabPage1").Enabled = False
        Me.getControl("TabPage2").Enabled = False
        Me.getControl("TabPage4").Enabled = False
        '// usw.
    End Sub
    Private Function getControl(ByVal name As String) As Control
        Dim t As Control
        For Each c As Control In Me.Controls
            t = Me.getControl(name, c)
            If Not t Is Nothing Then
                Return t
            End If
        Next
        Return Nothing
    End Function
    Private Function getControl(ByVal name As String, ByVal current_Control As _
      Control) As Control
        If current_Control.Name.ToUpper().Equals(name.ToUpper()) Then
            Return current_Control
        End If
        For Each c As Control In current_Control.Controls
            If c.Name.ToUpper().Equals(name.ToUpper()) Then
                Return c
            End If
            current_Control = Me.getControl(name, c)
        Next
        Return Nothing
    End Function