Get a Javascript variable in PHP

Question

I have a simple javascript code, that tells me if my website is in iframe.

<script>
if ( window.self === window.top ) { 
    var iframe = '0';
} else { 
    var iframe = '1';
}
</script>

How can I get the "iframe" variable from javascript, in php?

I want to do something like this:

<?php if ($iframe == "0") {
 //mysite for iframe
} else {
 //mysite general
}
?>

Is this possible?

PS.: I want to be SEO, too.

Thank you so much!!!

use should use ajax (or post form on server, or pass it through url parameter) — karaxuna, Aug 30 '13 at 07:58
you can do this test in a transitional page and then load your proper page later — DevZer0, Aug 30 '13 at 07:59
possible duplicate of [How to pass JavaScript variables to PHP?](http://stackoverflow.com/questions/1917576/how-to-pass-javascript-variables-to-php) — mumair, Aug 30 '13 at 08:00

score 3 · Answer 1 · answered Aug 30 '13 at 07:58

3

PHP is server side, Javascript is client side. You'll have to do something like Ajax to transfer the value from the web browser (Javascript) to the web server (PHP).

answered Aug 30 '13 at 07:58

PherricOxide

15,493
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Thank you, but how can I do this? – MM PP Aug 30 '13 at 08:00
1

Read some tutorials. It's simply too much to explain in just one answer on StackOverflow. – ciruvan Aug 30 '13 at 08:02

nl-x · Answer 2 · 2013-08-30T08:27:00.757

Since the order is:

-first parse PHP and send HTML to client
-then client runs Javascript that is in HTML

to do what you want will take multiple requests.

What you could do is:

-Load an HTML page that uses Ajax (a second request) to send the javascript variable to the server. The server then responds to the Ajax request with XML, and javascript should already know what to do with the answer.
-Load an HTML page that directly refreshes itsself, but sends along the javascript variable as a request variable (POST or GET). Something like:

<?php
    if (!isset($_REQUEST['iframe']) { // php checks if this it got the variable
        // it is not given yet, so let javascript refresh and give the variable
?>
        <script>
            var url = window.location.href.split('#')[0];
            var devider = url.indexOf('?') == -1 ? '?' : '&';
            var hash = typeof window.location.href.split('#')[1] == 'undefined' ? '' : '#' + window.location.href.split('#')[1];
            if ( window.self === window.top ) {
                window.location.href = url + devider + 'iframe=0' + hash;
            } else { 
                window.location.href = url + devider + 'iframe=1' + hash;
            }
        </script>
<?php
    } else {
        // it is given to php, lets do something with it...
        if ($_REQUEST['iframe'] == 1) {
            // ok, we're in an iframe. So what do you want to do?
        } else {
            // ok, we're not in an iframe. So what do you want to do?
        }
    }
?>

score 3 · Accepted Answer · answered Aug 30 '13 at 08:24

You can simple use:

<script>
    if ( window.self === window.top ) { 
            window.location = window.location + '?iframe=0';
    } else { 
            window.location = window.location + '?iframe=1';
    }
</script>

You said that you want to be SEO too, so you can put a canonical link rel in <head></head>:

<?php
$uri_parts = explode('?', $_SERVER['REQUEST_URI'], 2);
$canonical = 'http://' . $_SERVER['HTTP_HOST'] . $uri_parts[0];
?>

 <link rel="canonical" href="<?php echo $canonical; ?>"/>

This won't work if there are already request variables in the url. Also, SEO don't mind the stuff behind the ? ... So no need for the canonical. — nl-x, Aug 30 '13 at 08:30

score 2 · Answer 4 · answered Aug 30 '13 at 07:58

2

As Javascript is client side code and PHP is Server side code, the variables must somehow be passed to the server.

There are a few decent ways of doing this, by far the most common is GET and POST variables. then you can pick them up in php and do whatever you wish with it.

You may pass variables like this: file.php?EEEE=YYY then fetch that variable with

$_GET['EEEE']

answered Aug 30 '13 at 07:58

Iesus Sonesson

854
6
12

Thank you, i know that, but i want to do something seo. – MM PP Aug 30 '13 at 07:59
How does that change however the code is run on your server or in the browser of your visitor? – Iesus Sonesson Aug 30 '13 at 08:00
It runs from my visitor browser. – MM PP Aug 30 '13 at 08:02
PHP is run on the server (Hence server side) Javascript is run in the browser. In order to send something from visitor to server you need to use post, get or cookies with or without ajax – Iesus Sonesson Aug 30 '13 at 08:05

Eugene · Answer 5 · 2013-08-30T08:05:49.113

Looks like you can't. But you can send it with ajax to server and load requested changes:

if ( window.self === window.top ) { 
    var iframe = '0';
} else { 
    var iframe = '1';
    // here ajax requested that will load instructions about how to change a page
}

Or u can use window.location = url; for change url of page. For example you can add get parameter ?iframe=true and then use it in php:

if (isset($_GET['iframe'])) {
    // here something
}

score 2 · Answer 6 · answered Aug 30 '13 at 08:01

2

Check this out: Ajax

This is a short example of how to do Ajax calls, as PHP is run on the serverside, whereas javscript is clientside.

So essentially, your client function sends a request to the server, which then executes one of you PHP-implemented functions and returns the result.

answered Aug 30 '13 at 08:01

LuigiEdlCarno

2,410
2
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As a side note: W3Schools shouldn't be considered a good source for learning materials. – ciruvan Aug 30 '13 at 08:03

score 2 · Answer 7 · answered Aug 30 '13 at 08:03

Check out $_SERVER['HTTP_REFERER'], if the page is loaded from the frame, the refer should be different from the frame's src.

A quick test:

main.html:

<iframe src="frame.php"></iframe>

frame.php

echo $_SERVER['HTTP_REFERER'];

Visiting the page at main.html shows localhost/main.html while visiting at frame.php shows localhost/frame.php.

This is simply for SEO purposes, as this variable shouldn't be trusted for security reasons.

score 0 · Answer 8 · answered Aug 30 '13 at 09:19

You can do one thing make ajax call and send that variable to php file like At your javascript side==

jQuery.ajax({
            type: 'get', // type of request either Get or Post
            url: 'getValue.php', // Url of the file to set value in Session  
            data: "value="+iframe,  //that value which you want to use in php  
            success: function(data) 
            {}  });

At your php side

<?php session_start(); $val = $_GET["value"]; //receive data from ajax call $_SESSION['value']=$val; //set that value in session echo $_SESSION['value']; //way to access value which is stored in session ?>

now to access that value in php just need to write on the start of php file
session_start();
and access that variable using
$_SESSION['value'];
there is also another way i.e pass that variable through url e.g "http://www.example.com/index.php?value=123456"
in your index.php
$received_fr_url=$_REQUEST['value']; will take the value from url

Get a Javascript variable in PHP

8 Answers8