<?php
 
$users = array( 
        "username01" => array(  fullname => "Firstname Lastname",
                                status => "Online"),
        "username02" => array(  fullname => "Firstname Lastname",
                                status => "Offline")
         );
 
$string = "Online";
foreach ($users as $username => $data) {
  $fullname = $users[$username]["fullname"];
  $status = $users[$username]["status"];
  if($status == $string) { echo "Yes"; } else { echo "No"; }
}
 
?>

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