Finding Out Where Users Have Come From In PHP

12th December 2008 - 1 minute read time

Note: This post is over a year old and so the information contained here might be out of date. If you do spot something please leave a comment and I will endeavour to correct.

It is sometimes a good idea to find out where users can come from. When PHP is run the $_SERVER superglobal is always available and if the user has clicked on a link and landed on your page then the HTTP_REFERER value will be set. You can retrieve and view it on a test page like this.

if ( isset($_SERVER[ HTTP_REFERER ]) ) {
 echo $_SERVER['HTTP_REFERER'];
}

Of course you might want to do something useful with this. For example, you might want to know what link a user clicked on when they broke your application.

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