How to detect if a user has logged out, in php?

Question

After the user successfully logs in, I store login = true in database. But how do I check if the user logged out by closing the browser without clicking the logout button? A

Answer 1

Store the timestamp of each acitivity of the user. When that time is more than 10 minutes ago, do the logout.

In PHP, you could do something like this:

session_start();
if (!isset($_SESSION['LAST_ACTIVITY'])) {
    // initiate value
    $_SESSION['LAST_ACTIVITY'] = time();
}
if (time() - $_SESSION['LAST_ACTIVITY'] > 3600) {
    // last activity is more than 10 minutes ago
    session_destroy();
} else {
    // update last activity timestamp
    $_SESSION['LAST_ACTIVITY'] = time();
}

The same can be done on the database instead. There you could even get a list of users that are “currently” online.