how to auto refresh php page with jquery

as the question stated. everytime auto refresh 5s, its removing the session and give me the errors Notice: undefined variables in get_total_un_booking and get_total_un_booking.

before tag ive got php include and classes:

session_start();
require_once '../_include/user.inc.php';
require_once '../_include/booking.inc.php';
$user= new user;
$booking = new booking;
$getUser = $user->getUser($_GET['id_user']);
$getBookslot = $booking->get_bookslot($_GET['b_ref']);

HTML Nav:

<table id="nav">
<tr>
  <td><? include 'pages/nav.php'; ?></td>
</tr>
</table>

in Nav.php:

<? if($booking->开发者_运维百科get_total_un_booking() == 0) :
   echo '<a href="home.php?confirm"><span></span>Booking</a>';
?>
<? if($booking->get_total_un_booking() == 0) :
   echo '<a href="home.php?testimonial"><span></span>Confirm Testmnl</a>';
?>

jQuery:

$(document).ready(function(){
   setInterval(function() {  
        $("#nav").load('pages/nav.php');  
   }, 5000);  
 });

If you want access to the session variables in pages/settings.php , you must call session_start() on that page.

You can always transfer the session variable manually (presuming the JS comes from your PHP document):

$(document).ready(function(){
   setInterval(function() {  
        $("#content").load('pages/setting.php?PHPSESSID=<?=session_id();?>');  
   }, 5000);  
 });

Your code uses values from _GET array, but your .load() doesn't provide any - that's why there are undefined variables

<?php
    $id_user = $_GET['id_user'];
    $b_ref = $_GET['b_ref'];
?>
$("#nav").load('pages/nav.php?id_user=<?php echo $id_user?>&b_ref=<?php echo $b_ref?>')

Does your browser allow Cookies? I mean check your Browser configuration. And start the session handling on the server.

1°:

Test your to put session_start in the archives user.inc.php and booking.inc.php.

2°:

HTML:

<table id="nav">
<tr>
  <td class="update-ajax"><? include 'pages/nav.php'; ?></td>
</tr>
</table>

JS:

$(document).ready(function(){
   setInterval(function() {  
        $("#nav tr td.update-ajax").load('pages/nav.php');  // change selector
   }, 5000);  
 });