Multi-step page Redirector

post2get_redirect.php

<?php
// Make sure the form in your first step has a hidden field named "next_url"
// which should be the location of step 2 landing page, something like:
// "http://promos.mydomain.com/multi-step-form-2"
$redirect_to = $_POST['next_url'];
foreach($_POST as $key=>$value) { 
  if ($key != 'pageId' && $key != 'pageVariant' && $key != 'next_url') {
    $fields_string .= $key.'='.$value.'&'; 
  }
}
rtrim($fields_string,"&");
$url = $redirect_to . '?' . $fields_string;
header('Location: '.$url);
?>