Facebook fan page tab and user id.

Question

As per the documentation in the following link, we can get the user id if the uer will interact with the form..

http://wiki.developers.facebook.com/ind … d_Policies

"If a viewing user interacts with the tab (like submits a form, takes an action that causes an AJAX load of new content, or follows a relative URL that loads on the tab), that user's UID is sent to the application as the fb_sig_user parameter, the profile owner's user ID is sent as the fb_sig_profile_user parameter. The viewing user's session key is key is sent only if the user authorized the application. "

In my fan page tab am I have an AJAX form which the user can submit with some value.. now I need the users id also.. how can I get this..

I tried to get the value in my AJAX submit page using $_POST['fb_sig_user'] with no success.. can anyone help me with this please..

Answer 1

You won't be able to get the id of the user using $_POST['fb_sig_user'] unless you authenticate the user by having this in the facebook's ajax function:

ajax.requireLogin = true;

For example, I'm retrieving it fine with this:

function do_ajax(url, div_id)
{
    document.getElementById('poller_waitMessage').setStyle('display', 'block');

    var ajax = new Ajax();
    ajax.responseType = Ajax.FBML;
    ajax.onerror = function(error)
    {
        new Dialog().showMessage("Error:", "Some communication error occured, Please reload the page.","Ok");
    };

    ajax.ondone = function(data)
    {
        document.getElementById('poller_waitMessage').setStyle('display', 'none');
        document.getElementById(div_id).setInnerFBML(data);

    }

    ajax.requireLogin = true; // <----- this is important
    ajax.post(url);
}

Answer 2

I've been happily using the form variable fb_sig_profile_user for previous apps, and when developing a new app last week, the variable was no where to be found.

Searched for several days, I was about to give up, and then the found answer:

ajax.requireLogin = true;

I understand FB cares about privacy and all, but they really need to announce these kinds of changes before just taking it away.

Million Thanks!