Facebook getUser() returns 0 [duplicate]

Answer 1

I was stuck up with similar issue, here is the solution that may help you.

$facebook = new Facebook(array(
  'appId'  => 'xxxx',
  'secret' => 'xxxxx',
  "redirect_uri" => "set the uri to point to the same page"
 ));

$user = $facebook->getUser();

if($user)
{
//your task
} else {
header('location:'. $facebook->getLoginUrl());

}

$user = $facebook->getUser();

if($user)
{
//your task
} else {
header('location:'. $facebook->getLoginUrl());

}

Answer 2

I've encountered a similar problem. I used an example project, and couldn't figure out why it keeps returning 0. tried nearly all related links here but none solved it.

The solution was to update Facebook's SDK files in the example project. Simple and easily missed,

Answer 3

If App domain is real domain but site url is localhost, getUser function return 0

Answer 4

Came across a situation where getUser() was returning 0 when it really shouldn't be, the application was still sandboxed. Turns out the user hadn't accept the request to be developer of the application.

Answer 5

I had same issue, After long time of trying to figure out what the issue is, I found that you need access token to get user ID. To get access token form the signed_request, user must authorize (to get permissions) you app firstly. I hope this will help