facebook php-sdk 没有退出

Question

I'm having a hard time getting this to work. I use the following to generate the logout url:

$logout = "https://www.facebook.com/logout.php?next=" . urlencode('http://' . $_SERVER['SERVER_NAME'] . $_SERVER['PHP_SELF']) . "&access_token=" . $facebook->getAccessToken();

Which generates the correct (worked with the last version) url:

https://www.facebook.com/logout.php?next=http%3A%2F%2F...&access_token=AA....ZD

However this does not actually log the user out. I tried using

$facebook->getLogoutUrl(array('next' => 'myurl')) 

which generates pretty much the same url. This also did not work. I am lost as to why its not logging the user out. I actually tried manually putting the address into the address bar but it redirects me to the Facebook homepage.

Answer 1

The facebook php sdk uses php sessions to tokens that keep you logged in. To clear it, you can just destroy the session.

index.php:

<a href="logout.php">Log out</a>

logout.php

$facebook = new Facebook(array('appId'  => FB_APP_ID, 'secret' => FB_APP_SECRET, 'cookie' => true));
$facebook->destroySession();
header('location: index.php');

FB_APP_ID and FB_SECRET are my specific apps info. Replace with your own.

Answer 2

If you request the offline_access permission when using the Facebook PHP SDK (and sometimes even without it), it makes the default logout functionality not work very well. To fix this, following worked for me:

//change your logout url to 
$logoutUrl = $facebook->getLogoutUrl(array( 'next' => ($fbconfig['baseurl'].'logout.php') ));

//on logout page
setcookie('fbs_'.$facebook->getAppId(), '', time()-100, '/', 'domain.com');
session_destroy();
header('Location: /');

Answer 3

It could be because the PHP session and session cookie are still intact. I've written a short article that attempts to demystify FB login/logout at.