Add active class to active page

active.js

    $(function () {
      var pgurl = window.location.href.substr(window.location.href
        .lastIndexOf("/") + 1);
      $("nav ul li a").each(function () {
        if ($(this).attr("href") == pgurl || $(this).attr("href") == '')
          $(this).addClass("active");
      })
    });