<asp:Panel id="Panel1" runat="server">
    <table>
    .....
    </table>
</asp:Panel>
....如果破坏了页面排版就:
<table>
    <asp:Panel id="Panel1" runat="server">
        <tr>
        .....
        </tr>
    </asp:Panel>
</table>
....
在.CS中控制Panel的Visible属性即可!