Secure a page using php

By default php script runs on port 80 unless changed, but i had to secure a page so that it could run only on secure port i.e. 443. So what i did was used a code to force to run a page on secure port i.e. https which uses port 443, Here's what i did:

    $serverPort  = $_SERVER['HTTP_PORT'];
    //check if its not secure port
    if("443" != $serverPort) {
 header("Location: https://".$_SERVER["HTTP_HOST"] . $_SERVER["REQUEST_URI"]);
 exit;
    }
?>

So, the above code ensures that the page runs under https i.e. port 443 and
is securely displayed. Hope it helps someone.