Remove a cookie

Question

When I want to remove a Cookie I try

unset($_COOKIE['hello']);

I see in my cookie browser from firefox that the cookie still exists. How can I really remove the cookie?

Answer 1

Set the value to "" and the expiry date to yesterday (or any date in the past)

setcookie("hello", "", time()-3600);

Then the cookie will expire the next time the page loads.

Answer 2

See the sample labelled "Example #2 setcookie() delete example" from the PHP docs. To clear a cookie from the browser, you need to tell the browser that the cookie has expired... the browser will then remove it. unset as you've used it just removes the 'hello' cookie from the COOKIE array.

Answer 3

If you set the cookie to expire in the past, the browser will remove it. See setcookie() delete example at php.net

Answer 4

That will unset the cookie in your code, but since the $_COOKIE variable is refreshed on each request, it'll just come back on the next page request.

To actually get rid of the cookie, set the expiration date in the past:

// set the expiration date to one hour ago
setcookie("hello", "", time()-3600);

Answer 5

Thanks so far.

When I login I do:

setcookie("loggedin",true,time()+3600,'/');

And to logout i do

setcookie ('loggedin', false, time() - 4800,'/');

But appearantly when I want to check if I am logged it when I restart my browser I am not logged in. This is the way I check it:

if(isset($_COOKIE['loggedin']) and ($_COOKIE['loggedin'] == true) ){

Is this not the way to check if I am logged in?

Secondly, is there a way to combine cookies with sessions?

Answer 6

You could set a session variable based on cookie values

session_start();

if(isset($_COOKIE['loggedin']) && ($_COOKIE['loggedin'] == "true") ){ $_SESSION['loggedin'] = "true"; }

echo ($_SESSION['loggedin'] == "true" ? "You are logged in" : "Please Login to continue");

Answer 7

Note that the cookie and the session are completely unaware of each other. They are related, but detached.

Think about the session cookie like a ticket that let's you in and out of a nightclub. If you still have the ticket, but the club is closed you can't get back in. Like wise, if the club is still open but you lose your ticket you can't get in regardless.

Analogies aside, you don't kill a session by "unsetting" the cookie. You can trash the session with session_destroy, or if you want to log a user out just unset values held in the session that indicate that someone is logged in. You can let the browser keep the cookie if you like, it's just a useless ticket.