How to use class="Active" in navigation, If you are using static pages?

My Local Project for Getacho Company

I am working on my own company project. I am using Pixelogic static theme. I created different files for different website parts. like

1. Menu.php
2. Header.php
3. Footer.php

Like it. But here I was facing a problem in class="active" Code. It was like

---

 <nav class="navigation">  
   <ul class="sf-menu" style="float:left;">  
     <li class="active"><a href="index.php">Home</a>  
     </li>  
     <li><a href="about.php">About</a></li>  
     <li><a href="portfolio.php">Portfolio</a>  
     <li><a href="forums/">Forums</a>  
     </li>  
     <li><a href="blog/">Blog</a>  
     </li>  
     <li><a href="contact.php">Contact</a>  
       <ul class="sub-menu main-ul">  
       <li><a href="support/">Support</a></li>  
       <li><a href="support/">Live Chat</a></li>  
       </ul>  
     </li>  
     <li><a href="user/">User Panel</a>  
       <ul class="sub-menu main-ul">  
       <li><a href="user/seo/">SEO Panel</a></li>  
       </ul>  
     </li>  
   </ul>  
 </nav>  

But here I was getting some problem that how to move class="active" according to static current page.
Then I consulted with my friends and someone suggested me a code. now it is working.

Code was :

---

 <?php  
      $url = $_SERVER['REQUEST_URI'];  
      if (strpos($url,'about.php') !== false)  
           echo 'class="active"';  
 ?>  

Here you need to understand STRPOS function.
I used same code in my navigation. Now navigation is working good. Now navigation code is

---

 <div id="menu" class="clearfix">  
   <nav class="navigation">  
     <ul class="sf-menu" style="float:left;">  
       <li   
       <?php   
       $url = $_SERVER['REQUEST_URI'];  
       if (strpos($url,'index.php') !== false)  
       {  
       echo 'class="active"';  
       }  
       ?>  
       ><a href="index.php">Home</a>  
       </li>  
       <li   
       <?php   
       $url = $_SERVER['REQUEST_URI'];  
       if (strpos($url,'about.php') !== false)  
       {  
       echo 'class="active"';  
       }  
       ?>  
       ><a href="about.php">About</a></li>  
       <li   
       <?php   
       $url = $_SERVER['REQUEST_URI'];  
       if (strpos($url,'portfolio.php') !== false)  
       {  
       echo 'class="active"';  
       }  
       ?>  
       ><a href="portfolio.php">Portfolio</a>  
       <li><a href="forums/">Forums</a>  
       </li>  
       <li><a href="blog/">Blog</a>  
       </li>  
       <li   
       <?php   
       $url = $_SERVER['REQUEST_URI'];  
       if (strpos($url,'contact.php') !== false)  
       {  
       echo 'class="active"';  
       }  
       ?>  
       ><a href="contact.php">Contact</a>  
         <ul class="sub-menu main-ul">  
         <li><a href="support/">Support</a></li>  
         <li><a href="support/">Live Chat</a></li>  
         </ul>  
       </li>  
       <li><a href="user/">User Panel</a>  
         <ul class="sub-menu main-ul">  
         <li><a href="user/seo/">SEO Panel</a></li>  
         </ul>  
       </li>  
     </ul>  
   </nav>  
 </div>  

Guidance by :  Nahyan Shiwani