Custom SharePoint site menu

Codebehind.cs

protected readonly List<SubSite> SubSites = new List<SubSite>();

protected void Page_PreRender(object sender, EventArgs e)
{
    var siteMap = PortalSiteMapProvider.GlobalNavSiteMapProvider;

    var rootNode = siteMap.TryGetRootNode;

    SubSites.Add(new SubSite()
    {
        Title = rootNode.Title,
        Url = siteMap.CurrentSite.RootWeb.Url + "/m",
        IsCurrentSite = rootNode == siteMap.CurrentNode,
    });

    foreach (SiteMapNode node in rootNode.ChildNodes)
    {
        SubSites.Add(new SubSite
                               {
                                   Title = node.Title,
                                   Url = node.Url,
                                   IsCurrentSite = node == siteMap.CurrentNode,
                               });
    }
}

Markup.ascx

<div id="TopNav">
    <ul>
        <%foreach (SubSite site in SubSites) {%>
            <li><a href="<%=site.Url %>" class="<%=(site.IsCurrentSite ? "topnavselected" : "topnav") %>"><%=site.Title %></a></li>
        <%}%>
    </ul>
</div>