If you want to change the session id on each log in, make sure to use session_regenerate_id(true) during the log in process.
<?php
session_start();
session_regenerate_id(true);
?>
[Edited by moderator (googleguy at php dot net)]
session_destroy
(PHP 4, PHP 5, PHP 7, PHP 8)
session_destroy — Distrugge tutti i dati registrati in una sessione
Descrizione
session_destroy(): bool
session_destroy() distrugge tutti i dati associati alla sessione corrente. Non desetta nessuna delle variabili globali associate alla sessione o desetta il cookie di sessione.
Questa funzione ritorna true in caso di successo e
false in caso di fallimento nel distruggere
i dati di sessione.
Example #1 Distruggere una sessione
<?php
// Inizializza la sessione.
// Se state usando session_name("qualcosa"), non dimenticatevelo adesso!
session_start();
// Desetta tutte le variabili di sessione.
session_unset();
// Infine , distrugge la sessione.
session_destroy();
?>
Example #2 Distruggere una sessione con $_SESSION
<?php
// Inizializza la sessione.
// Se state usando session_name("qualcosa"), non dimenticatevelo adesso!
session_start();
// Desetta tutte le variabili di sessione.
$_SESSION = array();
// Infine distrugge la sessione.
session_destroy();
?>
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User Contributed Notes 4 notes
Praveen V ¶
12 years ago
Jack Luo ¶
10 years ago
It took me a while to figure out how to destroy a particular session in php. Note I'm not sure if solution provided below is perfect but it seems work for me. Please feel free to post any easier way to destroy a particular session. Because it's quite useful for functionality of force an user offline.
1. If you're using db or memcached to manage session, you can always delete that session entry directly from db or memcached.
2. Using generic php session methods to delete a particular session(by session id).
<?php
$session_id_to_destroy = 'nill2if998vhplq9f3pj08vjb1';
// 1. commit session if it's started.
if (session_id()) {
session_commit();
}
// 2. store current session id
session_start();
$current_session_id = session_id();
session_commit();
// 3. hijack then destroy session specified.
session_id($session_id_to_destroy);
session_start();
session_destroy();
session_commit();
// 4. restore current session id. If don't restore it, your current session will refer to the session you just destroyed!
session_id($current_session_id);
session_start();
session_commit();
?>
JBH ¶
7 years ago
I'm using PHP 7.1 and received the following warning when implementing Example #1, above:
PHP message: PHP Warning: session_destroy(): Trying to destroy uninitialized session in...
What I discovered is that clearing $_SESSION and removing the cookie destroys the session, hence the warning. To avoid the warning while still keeping the value of using session_destroy(), do this after everything else:
if (session_status() == PHP_SESSION_ACTIVE) { session_destroy(); }
greald at gmail dot com ¶
4 years ago
All of a sudden neither session_destroy() nor $_SESSION=[] were sufficient to log out. I found the next to work:
<?php
setcookie(session_name(), session_id(), 1); // to expire the session
$_SESSION = [];
?>
