取消分配$ _GET中的变量值

Question

I use;

$referrer = $_GET['_url'];

If I echo $referrer; it will display correctly.

If I use $referrer within a $_POST, it is empty. I think due to $referrer being assigned to $_GET.
How can I extract the value of $referrer into another variable so it is no longer assigned to the $_GET?

I hope that makes sense..

Answer 1

Use the clone keyword, as seen in the examples in this article: http://php.net/manual/en/language.references.php