facebook /me response undefinded -

there many posts "/me" returns undefined, couldn't find solution.

the user logged in, because response.status connected. calling /me returns "undefined".

code snippet:

if (response.status === 'connected') { // response object returned status field lets app know current // login status of person. in case, we're handling situation  // have logged in app.  fb.api('/me', function(info) { alert("facebook:"+info.id);  });