How to detect if the user is logout in php?

Question

After the user successfully logged in, I store login = true in database. But how do I check if the user logged out by close the browser without click the logout button? And somemore, how do I redirect user who has been inactive for 10 minutes to login page?

I am using php and mysql. Any help would be appreciated.

EDIT: Sorry if my question is not clear. I did use session to store whether they are loggin or not. But, now i want to store the info in database, so that i can display their status on other pages. Lets user1 has 3 friends. When display all his friends, he want to know whether his friend is online or offline. This is what I want. Any advise?

Answer 1

It might be better to store login=true in a session variable to check wheter or not the user is logged in. This would solve most of your problems ;)

Answer 2

Normally you would put such information in sessions.

$_SESSION['user'] = "A user name";

Then when you want to logout you do:

session_destroy();

Some more info on sessions here and a tutorial.

Answer 3

Why dont you use session or cookies for this instead of inserting it in the database. You can set the cookies by using setcookie() function or either you can make a session vaiable and store the value in it.

Answer 4

You would find it better to use the session to monitor the login status.

Read this information about sessions

Answer 5

You cannot detect when a user closes their browser or navigates off your site with PHP, and the JavaScript techniques of doing so are so far from guaranteed as to be useless.

Instead, your best bet is most likely to store each user's last activity time.

• Create a column in your user table along the lines of 'last_activity'.
• Whenever a user loads a page, update their last_activity to the current time.
• To get a list of who's online, just query the database for users with last_activity values more recent than 10/20/whatever minutes ago.

Answer 6

If you are trying to track the users that are 'online' then you might consider using a session for the individual user and instead of storing login=true in the db to display their status to you or others, store the last activity time for the user. When you pull up your list of online users, create your sql query to only return users with 'last_activity' within the last 10 minutes.

Answer 7

AFAIK there is no way for you to check when a person closes the browser window (or leaves you page to go to another) so you need to check activity as others suggested above.

Answer 8

You are wondering if you can detect if a user closed his browser. You kinda can with javascript but I would not rely on it (since javascript is easy to disable) But you can not with PHP, since PHP only runs when you are requesting a page. Not when the page is open.

To be safe you should track the user's last activity and if it's past a few minutes (5/10) then assume that user is gone. If he does something again though (after 6 minutes for example) then he's back online.

Answer 9

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.

Answer 10

This is an extension to what 'ceejayoz' said before.

Let the users periodically ping the service and tell that they are still logged in. Store last ping time in the session. If the last ping session is greater than a said time, then ping again to tell that the use is still alive.

Store the time when you received the ping in the database. If the last ping received is > the keeplive threshold then consider the user has left the site.

The following is some untested sample code for you start with. You can use the "PING__FREQUENCY" to control how often the frequency in which the user activity will update the last_activity column.

define(PING_FREQUENCY,300); //5 mins
if (($_SESSION['lastPingTime'] + PING_FREQUENCE) > time()) {
    stillLoggedIn(); //execute a function to tell that the user is still logged in
}

function stillLoggedIn() {
    //Do SQL update to mark the last activity time for the user
}

Answer 11

IMHO the best way is to store last activity timestamp in DB on each update of user record. After logoff or timeout (maintain timeouts with cronjob) just set it to zero-value and use as flag.

$user = new User($user_id);
$user->logged_in = (bool)($last_activity > 0);

Sometimes you will need to say smth. like "last seen on ...", then leave last activity and just add a boolean flag (tinyint) logged_in to your users table.

Answer 12

But how to make show logout user right after the close browser .

Answer 13

http://browserul-meu.ileapaulalexandru.ro/junk/script-de-detectare-a-userilor-online-in-php-in-timp-real.html