Panels and single page layout

Hi guys,
I hope this isn't something that gets asked all the time, but I can't seem to find the answer anywhere else.
I've written a project that uses multiple panels on one page as kind of the "Account page", the format is as below:

<Form runat="server"> <asp:Panel ID="PnCustomers" runat="server" visible="false"> -- Some content / controls </asp:panel> <asp:Panel ID="pnSuppliers" runat="server" visible="false"> -- Some content / controls </asp:panel> <asp:Panel ID="pnEmployees" runat="server" visible="false"> -- Some content / controls </asp:panel> etc... Then one the server side, something like this:
Protected sub Hide_All_Panels pnCustomers.visible = false pnSuppliers.visible = fals ...