如何将变量与HTTP_REFERER的第一部分进行比较？

Question

Please tell me, if I got a variable $var which returns: http://foo.com - then how can I check whether this uri is identical to what $referrer returns (given there is one), or to it's first part if $referrer = http://foo.com/oof/ or longer..?

With (any better way?):

$referrer = isset($_SERVER['HTTP_REFERER']) ? $_SERVER['HTTP_REFERER'] : '';

Basically I'd like to have an if/else case, for when the uri matches and when it doesn't. I'm also wondering how to it make hack-safe if you will, so that it can't be cheated when $referrer is fake like such: http://badsite.com/file.php?param1=http://foo.com, and so that here the http://foo.com part won't be considered a legit match.

Thanks a bunch!

Answer 1

To check the domain only:

$yoursite = ""; //Your site url without http:// or www.
$yoursite2 = ""; //Type your domain with www. this time

$referer = $_SERVER['HTTP_REFERER'];
$domain = parse_url($referer); 

if($domain['host'] == $yoursite || $domain['host'] == $yoursite2) {
     //Run your code here normally
}