Online PHP editor | output for K4hmv

<?php $str="HTTP/1.1 200 OK Cache-Control: private Transfer-Encoding: chunked Content-Type: text/abo Server: Microsoft-IIS/7.5 content-disposition: attachment; filename=_07412052_140822_140904.gpc X-Powered-By: ASP.NET X-UA-Compatible: IE=edge,chrome=1 Strict-Transport-Security: max-age=2592000; includeSubDomains X-XSS-Protection: 1; mode=block X-Frame-Options: sameorigin Frame-Options: sameorigin Date: Thu, 04 Sep 2014 19:03:29 GMT"; $pattern="Date"; $replace="ahoj"; echo preg_replace($pattern, $replace, $str);