Values between User Controls and ASPX Page

please email me if you have a solution
<%@ Master Language="C#" MasterPageFile="~/MasterPages/Root.Master" AutoEventWireup="true"
    CodeBehind="TwoColumn.master.cs" Inherits="NopSolutions.NopCommerce.Web.MasterPages.TwoColumn" %>
<%@ Register TagPrefix="nopCommerce" TagName="CategoryNavigation" Src="~/Modules/CategoryNavigation.ascx" %>
<%@ Register TagPrefix="nopCommerce" TagName="ManufacturerNavigation" Src="~/Modules/ManufacturerNavigation.ascx" %>
<%@ Register TagPrefix="nopCommerce" TagName="InfoBlock" Src="~/Modules/InfoBlock.ascx" %>
<%@ Register TagPrefix="nopCommerce" TagName="RecentlyViewedProducts" Src="~/Modules/RecentlyViewedProductsBox.ascx" %>
<asp:Content ID="Content1" ContentPlaceHolderID="cph1" runat="server">
    <div class="master-wrapper-side">
        <asp:ContentPlaceHolder ID="cph2" runat="server">
            <nopCommerce:CategoryNavigation ID="ctrlCategoryNavigation" runat="server" />
            <div class="clear">
            </div>
            <nopCommerce:ManufacturerNavigation ID="ctrlManufacturerNavigation" runat="server" />
            <div class="clear">
            </div>
            <nopCommerce:RecentlyViewedProducts ID="ctrlRecentlyViewedProducts" runat="server" />
            <div class="clear">
            </div>
            <nopCommerce:InfoBlock ID="ctrlInfoBlock" runat="server" />
        </asp:ContentPlaceHolder>
    </div>
    <div class="master-wrapper-center">
        <div class="master-wrapper-cph">
            <asp:ContentPlaceHolder ID="cph1" runat="server">
            </asp:ContentPlaceHolder>
        </div>
    </div>
</asp:Content>

The above is a nested master page.
I need to be able to get the values from the control
<nopCommerce:CategoryNavigation ID="ctrlCategoryNavigation" runat="server" />

there is a button on the control with cross page posting
to an aspx page. On that aspx I need the values from the control..