How to pass javaScript values to PHP

Question

How to pass javaScript values to PHP, my code is following

 <script>
    function a{
    var b = a;
    }
   </script>

<button onclick="a(2)">Values</button>

<?php
    $select = mysql_query("select * from tabl1 where id='values'"); // values comes here
    echo $select;
    ?>

Javascript run on client side (browser), your PHP code is on the server. If you want to pass JS variable to PHP you have to make a server call. AJAX seems to be the best answer here! Why do you want something else? — IsraGab, Apr 09 '16 at 19:59
Possible duplicate of [How to pass JavaScript variables to PHP?](http://stackoverflow.com/questions/1917576/how-to-pass-javascript-variables-to-php) — IsraGab, Apr 09 '16 at 20:07
Do NOT use `mysql_*` it has been removed and it will not work anymore, use `PDO` [link](http://php.net/manual/en/book.pdo.php) or `mysqli` [link](http://php.net/manual/en/book.mysqli.php) instead. — Tom, Apr 09 '16 at 20:35

score 0 · Accepted Answer · answered Apr 09 '16 at 20:32

There's a lot of thing you could do.

Principal things you have to know is that javaScript run on the client side (browser), while PHP is running on the server.

Then If you want to pass a variable from your JS to your PHP you have to make a server call.

There's various way you can use in order to send variable from client to server.

As I understand from your example, it looks like your php code and your javascript on the same file. so maybe call your file another time will be enough for you.

Let's say your file's name is index.php.

<script>
function yourJavascriptFunction(id) { 
  window.location.href = "index.php?id=" + id; 
}
</script>

Then in change your PHP code to this:

<?php
    $select = mysql_query("select * from tabl1 where id='".$_GET['id']."'"); // values comes here
    echo $select;
    ?>

$_GET will get the variable you've sent in your Js function.

Doing like this will refresh the page. May be you don't want to refresh the page? Then look at the ajax way.

I hope it helps you

How to pass javaScript values to PHP

1 Answers1