SharePoint Nested Menu Script

sharepoint-menu.js

var initMenu = function () {

    // Script compares document url with each menu url such that only those submenus that are children of the current page are toggled visible.
    // Compares both subfolders (Pages/folder/item.aspx) and subsites (site/Pages/folder/item.aspx) with url.

    // Hide all second-level menus.
    $('#DhssZenNav li.static ul').attr('style', 'display: none;');

    // Define regular expression.
    var myRegExp = new RegExp('(?:/|.*?//?.*?/)(?:pub/|home/)*((?:.*?/)*).*?.aspx');
    // note that ?: indicates an ignored block, (not passed to result array).
    // Breakdown:
    //  (?:/|.*?//?.*?/) => [ignored] / [or] http://, localhost/, etc
    //  .*?/             => [ignored] alaska.gov/, www.alaska.gov/
    //  (?:pub/|home/)*  => [ignored] pub/home/, pub/, home/
    //  (?:.*?/)*)       => [$1]      division/Pages/subfolder/anothersubfolder/
    //  .*?.aspx         => [ignored] default.aspx, test.aspx

    // Extract the folder uri from page URL and apply regular expression.
    var pageUri = myRegExp.exec(document.URL);
    pageUri = (pageUri && pageUri.length > 1) ? pageUri[1] : null;

    // If regular expression returns nothing or the site root, exit.
    if (!pageUri || pageUri === 'Pages/') return;

    // Iterate through all links in the menu.
    $('#DhssZenNav li.static > a').each(function (key, el) {
        // Extract folder uri from each link.
        var result = myRegExp.exec($(el).attr('href'));
        var linkUri = (result && result.length > 1) ? result[1] : null;
        if (!linkUri) return true; // Continue
        // Trim page uri to the length of the link uri, compare, and add the appropriate class on match.
        if (linkUri && pageUri.substr(0, linkUri.length) == linkUri) {
            $(el).parents('li').addClass('selected');
        };
    });

    // Add "selected" class to selected link's associated menu and show.
    $('#DhssZenNav li.static.selected > ul').addClass('selected').attr('style', '');
    // Add "active" class to selected link's parent menus and show.
    $('#DhssZenNav li.static.selected').parents('ul').addClass('active').attr('style', '');

}