Automatic Logout after 15 minutes of inactive in php

Question

I want to destroy session if users are not doing any kind of activity on website. At that time after 5 users automatically redirect on index page. How is it possible? Is pos

Answer 1

In index.php

in dashboard.php
if(time() - $_SESSION['loggedAt'] > 240) { 
    echo"";
    unset($_SESSION['username'], $_SESSION['loggedAt']);
    header("Location: " . index.php);
    exit;
} else {
    $_SESSION['loggedAt'] = time();
}