php - echo class "active" - if class="" is already exists or not. -

the following php function add class="active" current page open.

<?php #add class .active current page    $directoryurl = $_server['request_uri'];    $path = parse_url($directoryurl, php_url_path);    $components = explode('/', $path);    $currentpage = preg_replace("/\\.[^.\\s]{3,4}$/", "", end($components));     if ($currentpage == "") {        $currentpage = "index";    }     function href($url) {       global $currentpage;       $path = explode('/', $url);       $page = preg_replace("/\\.[^.\\s]{3,4}$/", "", end($path));       echo 'href="' . $url . '"';        if ($page == $currentpage) {          echo 'active';       }    } ?> 

here menu items:

<li><a class="icon-glass"<?php href('index.php');?>>home</a></li> <li><a <?php href('about.php');?>>about</a></li> 

the problem is, function works menu items has no class="" declared, i.e:

<li><a <?php href('about.php');?>>about</a></li> 

and not work one:

<li><a class="icon-glass"<?php href('index.php');?>>home</a></li> 

i believe part of script:

if ($page == $currentpage) {    echo 'class="active"'; } 

the question: how keep now, adding class="" when not added, add .active bit inside existed class (if found)?

i tried use echo 'active'; didn't work.

try format existing php code

<li><a class="icon-glass <?php href('index.php');?>">home</a></li> <li><a class="<?php href('about.php');?>">about</a></li> 

means have echo class active inside class property double quotes "".