preg replace - PHP preg_replace supplement link URL pattern -

i have following urls structure:

http://example.com/item/example-descriptions/6454986 http://example.com/item/example-bla-bla-bla/6545455 http://example.com/item/example-other-url/5454555 

i need add text numbers (add "/demo/" , "?id=test")

http://example.com/item/example-descriptions/demo/6454986?id=test http://example.com/item/example-bla-bla-bla/demo/6545455?id=test http://example.com/item/example-other-url/demo/5454555?id=test 

here couple of ways imperfect:

$myurl = 'http://example.com/item/example-descriptions/6454986';      if (substr_count($myurl, 'example.com')){     $url = "$myurl.html";        $url = preg_replace('/^(.*)\/([^.]+)\.html$/','$1/demo/$2?id=test', $url);       echo "$url";     } else {       echo "$myurl"; } 

and

$myurl = 'http://example.com/item/example-descriptions/6454986';      if (substr_count($myurl, 'example.com')){         $url = explode('/', $myurl);    echo "" . $url[0] . "/" . $url[1] . "/" . $url[2] . "/" . $url[3] . "/" . $url[4] . "/demo/" . $url[5] . "/?id=test";      } else {       echo "$myurl"; } 

help me improve code.

you can use parse_url:

if (parse_url($myurl, php_url_host) == 'example.com') {     $arr = explode('/', $myurl);     $arr[] = 'demo/' . array_pop($arr) . '?id=test';     $myurl = implode('/', $arr); }