Composit Control - Is Dispose Needed

[Auguy]

I have a composite control (with a button, a label, a checked list box, and two text boxes) that creates among other things a data view and 2 string builders. Do I need to dispose of these manually as in the following code? Or is this not necessary as they should be cleaned up when the form is closed?

 Private Sub SearchPanelCheckList1_Disposed(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Disposed
    cklDataSourceView = Nothing
    stbDesc.Length = 0
    stbDesc = Nothing
    stbPK.Length = 0
    stbPK = Nothing
End Sub

Auguy
Sylvania/Toledo Ohio