Get the URL users came from on an Error 404 Page using PHP?
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I'm currently building an Error 404 page for a website project. People are redirected to this page using .htaccess if the page they requested can't be found.

I want to display on the custom Error page the URL or link that they came from, but I can't figure out how. I had a go at this:

    <?php
    function curPageURL() {
      $pageURL = 'http';
      if ($_SERVER["HTTPS"] == "on") {$pageURL .= "s";}
      $pageURL .= "://";
      if ($_SERVER["SERVER_PORT"] != "80") {
        $pageURL .= $_SERVER["SERVER_NAME"].":".$_SERVER["SERVER_PORT"].$_SERVER["REQUEST_URI"];
     } else {
      $pageURL .= $_SERVER["SERVER_NAME"].$_SERVER["REQUEST_URI"];
     }
     return $pageURL; // Finally, Returns the page URL
    }
    ?>

And then I added the PHP function to my Error page:

    The Page You Came From Was: <?php echo curPageURL(); ?>

Sadly, all this does in the end is display the URL of my Error page, and not the one where users were just redirected from.

Anyone have any ideas?

Adam.