Stop Direct Access

Hello, I am using a few Ajax methods on a website... for gathering news, sending emails and updating profiles. Is there a way I can make a document that is used to gather the Ajax output not directly accessible?

I am submitting forms using action="[~xx~]" and I would like to make document xx not directly accessible if someone was to copy/paste the URL in to their browser.

I was thinking of doing my own idea using $_SESSION but wondered if someone else had already come up with something.

Thanks


*** I think I found out a way ***

check if the $_SERVER[’HTTP_REFERER’] is set or not. Seems to work