How to read jquery cookie value in php cookie value?

Question

I am not sure is it possible to read jquery cookie value in php cookie value?

var current = $.cookie("count");

    show<?php echo $keys; ?><?php setcookie("bgx","document.write(current)");  echo $_COOKIE["bgx"]; ?>now.play(); 

    $.cookie('count', <?php echo $count; ?>);

Yes, cookies created client-side with JavaScript are accessible by server-side PHP, these are just different ways to create and read cookies. The code you posted is not a very good example, though. _Note:_ for PHP to be able to read a cookie created with JS, you would first need to have the user visit the page, and only then, the cookie exists and can be read by PHP. Your JS is not being executed on the server-side. — blex, Jul 14 '15 at 10:37
I don't understand and if yes then how? This example not working @blex — FOOUTY, Jul 14 '15 at 10:39
How to executed those on server side? give me an example @blex — FOOUTY, Jul 14 '15 at 10:43
You mean when the user visit the page 2nd time then js cookie read by php ? @blex — FOOUTY, Jul 14 '15 at 10:46

blex · Accepted Answer · 2015-07-14T11:01:57.613

Here is a simple demo that shows how to create a cookie with JavaScript and read it with PHP when you reload the page (because JavaScript is executed after PHP, as it is client-side). Copy this code onto a new PHP document, upload it to your server, and try it.

<!DOCTYPE html>
<html>
<head>
    <meta charset="UTF-8">
    <title>Demo</title>
</head>
<body>

    <h1>Cookie demo</h1>

    <p>This demo shows how you can create a cookie with Javascript (using jQuery), and read it with PHP.</p>

    <?php

        /* THIS PORTION IS EXECUTED ON THE SERVER */

        // if the cookie "myCookie" is set
        if(isset($_COOKIE['myCookie'])){
            echo "<p><b>PHP found this value for <i>myCookie</i>: " .  $_COOKIE['myCookie'] . "</b></p>";
        }
        else{
            echo "<p><b>PHP did not find a value for <i>myCookie</i>. Give it a value below.<b></p>";
        }

    ?>

    <input type="text" id="myInput"/><button id="myButton">Change the cookie value using JS</button>

    <!-- make sure you load jQuery and the jQuery cookie plugin -->
    <script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.0.0-alpha1/jquery.min.js"></script>
    <script src="https://cdnjs.cloudflare.com/ajax/libs/jquery-cookie/1.4.1/jquery.cookie.min.js"></script>

    <script>

        /* THIS PORTION OF CODE IS ONLY EXECUTED WHEN THE USER SEES THE PAGE (CLIENT-SIDE) */

        $(function(){
            $('#myButton').click(function(){
                $.cookie('myCookie', $('#myInput').val());
                alert(
                    'The value of myCookie is now "'
                  + $.cookie('myCookie')
                  + '". Now, reload the page, PHP should read it correctly.'
                );
            });
        });

    </script>
</body>
</html>

@FOOUTY No problem, but make sure to check out Quentin's answer, which explains the problem really well. This is just a demo, but he has the explanation, consider accepting his instead of mine ;) — blex, Jul 14 '15 at 11:14
@FOOUTY Yes. More info info here: http://stackoverflow.com/questions/2163828/reading-cookies-via-https-that-were-set-using-http — blex, Jul 14 '15 at 11:33

score 2 · Answer 2 · answered Jul 14 '15 at 11:11

A cookie is a piece of data that is stored in a browser and associated with a website. Every time the browser requests something from a website, it includes the cookies in the request headers.

You can read and write cookies with client side JavaScript. (NB: It is possible to mark cookies as http_only, in which case they can't be read with client side JS).

You can read (by examining the request headers) and write (using response headers) cookies with server side code.

The usual rules of timing apply:

show<?php echo $keys; ?><?php setcookie(

Setting a cookie with server side code requires you to issue a response header. PHP doesn't let you issue response headers after you have started outputting the response body.

You are trying to call setcookie too late. You need to call it before you start outputting any content.

"document.write(current)"

I'm not sure what you are trying to achieve here.

It doesn't make much sense to store JavaScript code in a cookie.
You can't generate server side code using client side code, so if this is an attempt to write the value of current into a cookie, then it is too late.

setcookie("bgx","document.write(current)"); 
echo $_COOKIE["bgx"];

$_COOKIE is populated with data from the request.

It won't have data in it that your current response is about to ask the client to store. You won't get that new value until the next request.

In short: To read a cookie set with JavaScript, you have to make a new HTTP request after you have set it.

How to read jquery cookie value in php cookie value?

2 Answers2