How to use preg_match?

Hello, I have a problem getting user id from this string using preg match... what am I doing wrong?

<?php            $edituser = "http://localhost/wp_users/user-edit.php?user_id=39&wp_http_referer=%2Fwordpress%2Fwp-admin%2Fusers.php%3Fs%3Dingrid%40gmail.com%26action%3D-1%26new_role%26paged%3D1%26action2%3D-1";
            
            preg_match('/user-edit.php?user_id=([a-z|0-9]+)&/', $edituser, $matches);
            echo $matches[1];
?>

Code (markup):

Notice: Undefined offset: 1 in /var/www/teststuff.php on line 5

 

try this :

$url = 'http://localhost/wp_users/user-edit.php?user_id=39&wp_http_referer=%2Fwordpress%2Fwp-admin%2Fusers.php%3Fs%3Dingrid%40gmail.com%26action%3D-1%26new_role%26paged%3D1%26action2%3D-1';


$QUERYVAR= parse_url($url, PHP_URL_QUERY);


$GETVARS = explode('&',$QUERYVAR);


foreach($GETVARS as $string){
     list($is,$what) = explode('=',$string);
     echo "$is -> $what<br/>";
}

Code (markup):

if you just want the user_id value, you can take the first output only :

$url = 'http://localhost/wp_users/user-edit.php?user_id=39&wp_http_referer=%2Fwordpress%2Fwp-admin%2Fusers.php%3Fs%3Dingrid%40gmail.com%26action%3D-1%26new_role%26paged%3D1%26action2%3D-1';


$QUERYVAR = parse_url($url, PHP_URL_QUERY);


$GETVARS = explode('&',$QUERYVAR);


list($a,$user_id) = explode('=',$GETVARS[0]);


echo $user_id;

Code (markup):

 

Your regex pattern won't find your user_id. If it's a WordPress URL, the user_id will always be an integer, so you can use \d in your pattern.
You also don't need to include '/user-edit.php?' because what happens if user_id is not the first variable?
And as you use \d you can leave the '&' symbol from your pattern, so it will also find the id if it's the last element.

See below:

$edituser = 'http://localhost/wp_users/user-edit.php?user_id=39&wp_http_referer=%2Fwordpress%2Fwp-admin%2Fusers.php%3Fs%3Dingrid%40gmail.com%26action%3D-1%26new_role%26paged%3D1%26action2%3D-1';

preg_match('#user_id=([\d]+)#', $edituser, $matches);

echo $matches[1];

PHP: