how to pass the javascript variable to php variable inside a javascript function

Question

i know this is too dumb to ask. but i'll still ask this question..

i know how to pass the php variable to javascript variable inside the javascript function

function foo(){
var bar = <?php echo $foo; ?>
}

But how about from php variable to javascript inside a javascript function.

function foo(){
var bar;
<?php echo $foo; > = bar;
}

is this correct? because my javascript function is not working..

use ajax to send javascript variable to server. – Ajeet Sinha Nov 01 '13 at 04:03 — Ajeet Sinha, Nov 01 '13 at 04:03
no . im using to alert it .. – Vincent Nov 01 '13 at 04:12 — Vincent, Nov 01 '13 at 04:12

score 1 · Accepted Answer · answered Nov 01 '13 at 04:07

1

If you do want to use PHP, always encode with json_encode before outputting.

<script>
    var myvar = <?php echo json_encode($myVarValue); ?>;
</script>

answered Nov 01 '13 at 04:07

Jenz

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what if the variable in php is a database array. should i do this? var myvar = new Array(); myvar = ; is this right? – Vincent Nov 01 '13 at 04:11
1

Try to alert the array as alert(); – Jenz Nov 01 '13 at 04:15

score 0 · Answer 2 · answered Nov 01 '13 at 07:56

0

What you're trying to do is not possible. Remember that PHP runs on the server and renders the page to the browser. Only after the browser has received the finished PHP output does any Javascript on the page execute.

To pass JS variables into PHP you have to send them back to a script on the server using AJAX, and then do something in JS with the PHP result.

answered Nov 01 '13 at 07:56

joshstrike

1,753
11
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oh. now i understand why everytime i send a data to the server using php. the value(php variable) in my javascript doesnt change. im having a little problem here. like passing a value using only a div. after that. the div will refresh. that div has a script inside. like
.. the php refreshes and change it's value. but the the value in javascript doesnt change. oh no... what should i do... – Vincent Nov 02 '13 at 01:38

how to pass the javascript variable to php variable inside a javascript function

2 Answers2