How to assign value to $_SESSION with AJAX?

Question

Yes, I'm aware that this question has already been post, but ... I'm looking for a way to check if the Client has Javascript Enabled.

Here is my idea : At every loading page, PHP initialize $_SESSION['is_js'] to 0. Then, I wish AJAX to (via launching a script php ?) try to set $_SESSION['is_js'] to 1. If JS is enabled, AJAX will succeed, if not, the value remains 0.

I can't use jQuery or others libraries... I have to write this in pure AJAX (I mean not using framework or librairies), and I have no idea how to do this.

Edit : I can't use cookie. I don't want to use <noscript>.

http://stackoverflow.com/questions/121203/how-to-detect-if-javascript-is-disabled - read that first and please stop misusing AJAX.. you can't "write something in PURE AJAX", that makes no sense at all. It's not a programming language, and mostly you don't even use X part of AJAX nowadays. — N.B., Feb 13 '12 at 16:39
Powerfull comment MetalFrog. @N.B. : well, I express myself very bad. I will edit. — 4wk_, Feb 13 '12 at 16:41
I don't want to use `` cause I need the information (is JS enabled, checked at every loading) in every page. — 4wk_, Feb 13 '12 at 16:46
Build using [progressive enhancement](http://en.wikipedia.org/wiki/Progressive_enhancement) and you won't need to check that any more. — Quentin, Feb 13 '12 at 16:51
This is starting to sound like a homework assignment. Why are you so restricted on all the common, useful tools? — Mikhail, Feb 13 '12 at 16:51
AJAX = "asynchronous Javascript and XML". What you want is Javascript + PHP. In addition, if you cannot use cookies then the only thing left is that nasty old GET params passing. — Xeoncross, Feb 13 '12 at 16:51
Can you explain why you can't use a cookie? Using a cookie is a much better solution than using ajax so perhaps it's better to find a way of overcoming the reason why you can't use cookies. — wheresrhys, Feb 13 '12 at 16:51
Mikhail : Sometimes, for a particular client, you just CANT what you want ... Xeoncross : some guys tell me that JS (without AJAX) can't interact at all with PHP. — 4wk_, Feb 13 '12 at 16:57
Quite odd that the client is instructing the expert on how to implement something, isn't it? I'm not telling my car mechanic **how** to fix my car, I pay him to do it. — N.B., Feb 13 '12 at 17:04

Nettogrof · Accepted Answer · 2012-02-13T16:54:47.957

1

First you need to learn to do a ajax call in pure javascript, some website like w3schools or others

And in the php files that the ajax call , you can set the session variable to 1.

But there's maybe better way to find if the client have javascript enable.

EDIT: I suggest to check if your session variable is , if not, try the ajax call and set the variable at 0 . If at page loading the variable is set and equal, that means the client doesn't have javascript/xmlhttprequest enable.

And for a session, a cookie is store on the client side. So if the client refuse to store any cookie, you will never haver information in your session variables.

edited Feb 13 '12 at 16:54

answered Feb 13 '12 at 16:35

Nettogrof

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I looked for any better way for that, but I didn't. Let me know if you found something better ! – 4wk_ Feb 13 '12 at 16:37
@Ash_ Oh your question is : you want to find the best way to check if client have javascript enable ? – Nettogrof Feb 13 '12 at 16:43
Yes but I would specify "at every loading page" : I want to have this information in PHP all the time (except first connection, of course) – 4wk_ Feb 13 '12 at 16:48

Mikhail · Answer 2 · 2012-02-13T16:47:25.180

0

I would use a cookie. It will function nearly identical --

<?php
$_SESSION['js'] = (int) $_COOKIE['js']
setcookie('js', 0);
?>
<script type="text/javascript">
setCookie('js', 1);
</script>

You can use a set of cookie functions such as http://www.w3schools.com/js/js_cookies.asp

Good luck!

edited Feb 13 '12 at 16:47

answered Feb 13 '12 at 16:32

Mikhail

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PHP function is `setcookie()`, not `set_cookie()`. Also, quoting w3schools as a relevant source is a big no, that site is so full of misinformation that it's not worth reading anything there. Other than that, the idea is good. – N.B. Feb 13 '12 at 16:40
2

@Ash_, if you can't use cookies then SESSIONS won't work -- they rely on cookies – Mikhail Feb 13 '12 at 16:45
Well, of course I use cookies throw $_SESSION, but I don't want to use $_COOKIE because data is transmitted in HTTP header. (that is not the case of $_SESSION) – 4wk_ Feb 13 '12 at 17:00

score 0 · Answer 3 · answered Feb 13 '12 at 16:54

0

A rather unique (and IMO lame) approach is to use javascript to download a fake image:

<script type="text/javascript">
var fake = new Image();
fake.src = "/sess_js.php";
</script>

Doesn't use AJAX, jQuery, Cookies, etc.

answered Feb 13 '12 at 16:54

Mikhail

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score 0 · Answer 4 · answered Feb 13 '12 at 17:45

According to your idea and your requirements, if you can't use a library like jQuery or Prototype, and so on... you are enforced to use the "raw" XMLHttpRequest Object. The following code is an example.

Create a file called ajax_js_enabled_test.php and put this code inside:

<?php

    if(isset($_GET['PHPSESSID'])) session_id($_GET['PHPSESSID']);
    session_start();

    if(isset($_SESSION['user_js_support']) && $_SESSION['user_js_support']) echo "Javascript enabled";
    else $_SESSION['user_js_support'] = FALSE;

?>
<script type="text/javascript">
    var XHR;
    if (window.XMLHttpRequest){
        // The code for IE7+, Firefox, Chrome, Opera, Safari
        XHR=new XMLHttpRequest();
    }else{
        // The code for IE6, IE5
        XHR=new ActiveXObject("Microsoft.XMLHTTP");
    }
    XHR.open("GET","http://127.0.0.1/check_js_user_support.php<?php echo '?PHPSESSID='.session_id(); ?>",true);
    XHR.send();
</script>
<p>
    <a href="<?php echo '?PHPSESSID='.session_id(); ?>">
        Refresh
    </a>
</p>

Create another file called check_js_user_support.php and put this code inside:

<?php

    if(isset($_GET['PHPSESSID'])) session_id($_GET['PHPSESSID']);
    session_start();

    $_SESSION['user_js_support'] = TRUE;

?>

Copy both files in your local web server root. Open the page ajax_js_enabled_test.php from your browser. The AJAX request starts and the page check_js_user_support.php will set the session param called user_js_support to TRUE. So by pushing the Refresh button the page will be reloaded, the $_SESSION['user_js_support'] will be TRUE and the script will write: "Javascript enabled"

How to assign value to $_SESSION with AJAX?

4 Answers4