How to convert an SEO friendly URL to a PHP page

Question

I would like to show my page URL:

www.mypage.com/?q=picture

Instead of:

www.mypage.com/picture.html

I don't know how to redirect the page I want to see. But the url should not show page extension I have tried something like this but it's not working:

<a href="?q=home" style="text-decoration: none; color: #1E90FF; font-size:25px;">Home</a>
<?php
if(isset($_GET['q']) && $_GET['q']!="" )
    {
        $ext=".php";    
        $page=$_GET['q'].$ext;
        if(file_exists($page))
        {
            header('location:$page');
        }
        else 
        {
            header('location:errorpage.php');
        }
    }    
 ?>

Answer 1

Use .htaccess. Create a file called .htaccess and add the code below. Hope this works

#rewrite file
RewriteEngine on

RewriteRule ^?q=([0-9a-zA-Z]+) $1.html

The only problem is that i could go to www.mypage.com/?q=mario and it will look for mario.html.

If that doesn't work then uses this.

#rewrite file
RewriteEngine on

RewriteRule ^home home.html
RewriteRule ^picture picture.html

this will make www.mysite.com/picture display all the content just like viewing picture.html