Printed September 9, 2010 from B&T's Tips & Scripts
http://tips-scripts.com
Stop direct links to web pages
Want to stop someone from entering your site unless they come in the "front door"? Or want to keep a frame page from being loaded outside of the frameset? This script example will not let you load page2 unless you have already loaded page1 in the same browser session.
page1.php has this script:
<?php
session_start();
$_SESSION['valid'] = "yes";
echo "Page 1";
?>
page2.php has this script:
<?php
session_start();
if ($_SESSION['valid'] != "yes") header("Location: page1.php");
echo "Page 2";
?>