<script runat="server">
Sub Button1_Click(sender As Object, e As EventArgs)
??Response.Write("The naming container is: ")
??Response.Write(button1.NamingContainer)
End Sub
</script>

<form runat="server" >
<asp:Button ID="button1" OnClick="Button1_Click"
Text="Get NamingContainer" runat="server" />
</form>