PHP var in javascript?

Question

I am trying to use a php variable in my javascript code, but i cant seem to get it working. Here is my js and php code:

<?php $s = "woo"; ?>
var images = <?=$s?>;

What i want to achieve, is a php variable in javascript ENCLOSED with ['']; With other words, so that the javascript code reads it like this: ['woo']; I could really need some help, as i am very new to javascript. Thanks in advance.

create a quote inside your javascript. Please use standard and a readable php coding. — NosiaD, Apr 20 '14 at 02:45
Remember that you can "view source" on the page to see the exact JavaScript that's being rendered by the PHP. — Brian Kendig, Apr 20 '14 at 03:03

score 1 · Answer 1 · answered Apr 20 '14 at 03:07

I recommend using json_encode for all values "passed" to JavaScript - this will prevent against injection, accidental or otherwise. It also trivially handles quotes and allows complex object graphs to be supplied. If not already, I imagine that images is really, or should be, an array ..

var images = <?= json_encode($s) ?>;

Or

var images = <?php echo json_encode($s); php?>;

Look at the actual HTML to see what is being emitted, and that it is valid - the original yields JavaScript akin to var images = woo;, which will result in a ReferenceError (on woo).

score 0 · Answer 2 · answered Apr 20 '14 at 02:55

0

One trick you can use is this, when you are inside a .js file it can be helpful, because php doesnt work.

Put the value of your php value inside a div as content, and then grab that in the javascript.

in the php file:

<div id="sVar" style="display:none;"><?php echo $s; ?></div>

in js:

var images = document.getElementById('sVar').innerHTML;

answered Apr 20 '14 at 02:55

Andrew

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This did not work, weirdly enough. – MOLOCOG Apr 20 '14 at 02:59
Does your php file load before the javascript runs, if not it wont have a div of that id to grab. – Andrew Apr 20 '14 at 03:01

PHP var in javascript?

2 Answers2