php - How do I check if the request is made via AJAX in CodeIgniter?

Question

How do I check if the request is an AJAX? I am using CodeIgniter. I have a link that when it clicked, it'll open the pop-up dialog window this is done through ajax it requests to a controller name login_window().

CodeIgniter

//Here is the controller name:
function login_window(){
    // request via ajax
    $this->load->view("login_window");
}

jQuery

//here is the jquery code:
//I am using a jquery plugin FACEBOX

$('a[rel*=dialog]').facebox();

<a href="http://localhost/codeigniter/login_window" rel="dialog">Login</a>

I want to check if it is an AJAX request and if not, i will redirect them to homepage. so there's no way they can access the page that is intended only for ajax requests.

Answer 1

If you are using a library that sends the X-Requested-With header, then you can do...

if (strtolower(filter_input(INPUT_SERVER, 'HTTP_X_REQUESTED_WITH')) === 'xmlhttprequest') {
   // I'm AJAX!
}