source of REQUEST

问题:

How do I get the url from which the request was submitted. I tried $_SERVER['REQUEST_URI']; but this gives me the destination url not the source url. Is it possible to get the origin?

回答1:

You are looking for $_SERVER['HTTP_REFERER'];

Note:

The address of the page (if any) which referred the user agent to the current page. This is set by the user agent. Not all user agents will set this, and some provide the ability to modify HTTP_REFERER as a feature. In short, it cannot really be trusted.

回答2:

$_SERVER['HTTP_REFERER'] will work, if it is provided by the calling browser. Note that it is provided by the client so it may be empty or faked, so don't trust it security-wise.