How to get the url of the previous page-php Tutorial

How can I get the url of the previous page? I use header (Location :.. index. php) jump to index. for php, how can I obtain the url of the page before the jump? it seems impossible to use $ _ SERVER [HTTP_REFERER. ------ Solution ------------------ pass the url during the jump, for example, PHPcode $ pre_urlurl_encod how to get the url of the previous page
I jumped to index. php through header ('Location: ../index. php'). how can I get the url of the page before the jump,
$ _ SERVER ['http _ referer'] does not seem to work.

------ Solution --------------------
The url is uploaded during a jump, for example

PHP code

$ Pre_url = url_encode ('http: // 127.0.0.1/xxx. php'); header ('Location: ../index. php? Pre_url = '. $ pre_url );