How does request::is_ajax() work in Kohana?

Question

How does Kohana determine if a request is an AJAX one?

Is there anything different in the referrer string? Do I need to add a GET param, perhaps ?ajax=true ?

Answer 1

It checks if the request is made by XMLHttpRequest since most browser send a header in this case with this indication: header HTTP_X_REQUESTED_WITH would be set to XMLHttpRequest.