Programatically adding nodes to Top Navigation Control

Scenario:
You want to programatically add node to Top Navigation Control

Solution:
You can add child nodes to Site Collection's TopNavigationBar

Code:

using (SPWeb site = new SPSite("http://localhost")) {

    SPNavigationNodeCollection topNav = site.Navigation.TopNavigationBar;

    // create top navigation tab & add to top nav bar
    SPNavigationNode topNavMenuItem = new SPNavigationNode("Site Collection Galleries", string.Empty, false);
    topNav[0].Children.AddAsLast(topNavMenuItem);

    // create first drop down pointing to Master Page Gallery
    SPNavigationNode mpg = new SPNavigationNode("Master Page Gallery", string.Format("{0}/_catalogs/masterpage", site.Url), true);
    topNavMenuItem.Children.AddAsFirst(mpg);

    // create first drop down pointing to Web Part Gallery
    SPNavigationNode wpg = new SPNavigationNode("Web Part Gallery", string.Format("{0}/_catalogs/wp", site.Url), true);
    topNavMenuItem.Children.AddAsLast(wpg);

   // create first drop down pointing to List Template Gallery
   SPNavigationNode ltg = new SPNavigationNode("List Template Gallery", string.Format("{0}/_catalogs/lt", site.Url), true);
    topNavMenuItem.Children.AddAsLast(ltg);

   // create first drop down pointing to Site Template Gallery
   SPNavigationNode stg = new SPNavigationNode("Site Template Gallery", string.Format("{0}/_catalogs/wt", site.Url), true);
    topNavMenuItem.Children.AddAsLast(stg);

  // commit the changes
   site.Update();
}

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