Set and update cookie by a select form

[etrader]

I want to update a value by setting cookie. I use this code:

 

<?php
    if (isset($_POST['ChangeOrdering'])) {
        setcookie("Ordering", $_POST['ChangeOrdering'], time() + 31536000);
    }
echo $_COOKIE["Ordering"];
?>

<form method="post" action="<?php echo $_SERVER["PHP_SELF"] ?>"> Reorder messages:
<select name="ChangeOrdering">
<option value="DateAdded ASC">Oldest first</option>
<option value="DateAdded DESC">Newest first</option>
<option value="Title ASC">By Title, A-Z</option>
<option value="Title DESC">By Title, Z-A</option>
</select>
<input type="submit" value=" Save Settings " />
</form>

 

Problem is that echo will return the previous cookie set, not the last value. As a matter of fact, my problem is about updating the cookie. It seems that the browser load the cookie before it is updated by the POST value.

[Pikachu2000]

The value of a cookie is not available until the next page load.

 

Once the cookies have been set, they can be accessed on the next page load with the $_COOKIE or $HTTP_COOKIE_VARS arrays.

[etrader]

One time the page is load when submitting the form. Is it possible to avoid this page load by a method other than <form> to set the cookie? Or I need to use AJAX to set the cookie without page load?