Question

I would like to set php session with ajax.
there is my function to set session in session.php.

public static function set($key, $value) {  
    $_SESSION[$key] = $value;
}

and I have confirm javascript alert and if I click on yes, i want to set session.
How can I set session simply?

EDIT 16.4.2012 15:31 GMT:+1

David: thanks for an answer, it looks clearly. I tried it, but doesn´t do anything at my pc. So I have: a.php

<script src="http://code.jquery.com/jquery-latest.js"></script>
<p>I would like to say: </p>
<script>
    $("p").append("<strong>Hello</strong>"); //check jquery is working 
    $.get('a.php', function(data) {
        // do something on success?
    });
</script>

b.php (in same folder)

<script type="text/javascript">
    alert('aaa');
</script>
<?php
echo "print by b.php";
?>

and I run a.php in browser

Answer 1

You can have a simple PHP page which does nothing more than set the value (using the code you already have), and then have jQuery call that page:

$.get('setsessionvalue.php', function(data) {
  // do something on success?
});

If you want to expand it, you can make the call more general by passing values on the query string:

$.get('setsessionvalue.php?key=someKey&value=someValue', function(data) {
  // do something on success?
});

Then you’d pull those query string values from the $_GET collection on the server just like any other page.

From the server-side code’s perspective, it’s not different than any other page. You just don’t need to render a UI (and can render data if you want, probably easiest in JSON format). The JavaScript code is just calling that page like any other page.

It’s worth noting, of course, that a user can call this page manually if they want to. So don’t use this as any kind of “security” for session values. If a user goes to the URL:

setsessionvalue.php?key=someKey&value=someValue

then they would be able to set their session values manually. Even overriding the values you’ve already set (which they can see in the JavaScript code). I wouldn’t be particularly comfortable exposing the structure of session values (especially their keys) to client-side code like that. It seems like a short distance away from having some security holes in your site.