how to indentify "HTTP_REFERRER"

sfullman

In ASP a long time ago I remember being able to identify the HTTP referrer (i.e. where the user came from). I realize all browsers don't support that and it's not critical. But searching globals I can't find this one. Isn't there something like this in PHP?

thanks,
Sam

cgraz

yes, it's $_SERVER['HTTP_REFERER']

http://www.php.net/manual/en/reserved.variables.php

Cgraz

epp_b

That, or simply $HTTP_REFERER. (yes, that is purposely spelled with ONE r (referer), and NOT two r's (REFERRER)).

Be careful with this, though. Not all browsers will supply this variable to the server, so don't rely on it heavily if you are using it for security purposes.

cgraz

that's assuming globals are on. They're set to off by default.

Cgraz

epp_b

Yes, of course, Globals must be on.

Obviously, there set to on over here 😃

cgraz

lol mine are set to on too (the host's settings). But it's always best to assume that they're set to off when dealing with other people's servers. sfullman's server might have it to off, whereas $_SERVER['HTTP_REFERER'] would work but $HTTP_REFERER would not. 😃

Cgraz

enterume

Correct me if i am wrong.

Can I said that $_SERVER['HTTP_REFERER'] or $HTTP_REFERER is client's browser dependancy, like it doesn't support?

I am using PHP4.3+Apache 1.3.x , global set to on. I couldn't get any value return for $HTTP_REFERER. What's the problem?

diego25

$HTTP_REFERER will only be defined when there IS a referrer. So if you tested by just typing your script's name in the URL bar, then there's no referrer really, so HTTP_REFERER won't be defined. So to test your script, you should create 2 pages. One page will just output HTTP_REFERER, and the second page will just be an HTML page with a link to the PHP script. So you type the URL of the HTML page in the URL bar, click on the link, and now there should be a HTTP_REFERER. And yes, it is browser-dependent...it's up to the browser to send it or not.

Diego