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how to get if person is already liked fb page or not using javascript sdk

I intergrate like button in my website. After login with facebook, now if any one already liked fb page directly from facebook then some fields will be shown to user otherwise fields will be hidden. I already put function for above thing and it works for me but not for others. Don't know why?
Here is a function which contains fb like thing and triggered on button click
function getUserDetail(){
FB.api("me/likes/242500342443159", function(response) {
if ( response.data.length == 1 ) {
$('#myModal').modal('show');
getUserInfo();
document.getElementById("note").style.display="none";
console.log('You like it');
} else {
$('#myModal').modal('show');
getUserInfo();
document.getElementById("form").style.display="none";
console.log("You don't like it");
}
});
}
and i also took user_likes permission on login.
Please correct me if i am doing any mistake in above function.

IMPORTANT: You are not allowed to hide/gate content behind a like or incentivize liking a Page in any way. you must read the platform policy before creating any App: https://developers.facebook.com/policy/
That being said, you would need user_likes for that API call, which needs to get reviewed by Facebook before everyone can use it. Without review, only users with a role in the App are able to authorize that permission. It is called Login Review: https://developers.facebook.com/docs/facebook-login/review

If you got permission for your application, and got premission from the logged in user, but it still doesn't work I would sugest creating error handling and in case of debugging log the response object.
Check for error codes and response format: https://developers.facebook.com/docs/graph-api/reference/user/likes/

How to detect login window close event on LinkedIn Javascript SDK?

I am using LinkedIn Javascript SDK to log my users in, and I need to detect if a user closes the login/auth window before they complete the login or authorization. Current SDK doesn't fire the login callback when the window is closed (I naturally expect it to be called with IN.User.isAuthorized() set to false just like in Facebook Javascript SDK).
How can I detect when the user closes the Login with LinkedIn window?

The LinkedIn API is a bit of a nightmare to deal with.
I had a similar issue where it was firing multiple requests if they opened the auth window more than once. I solved this by adding a count each time they opened the window and then ignoring everything if count > 1. My solution involves Angular and Promises so I'm not going to post the full solution.
For you, I would just add authTriggered and authComplete variables. The triggered gets set when they click they link/button to authorise with LinkedIn and the complete variable gets set in the auth callback.
Something like this perhaps?
var LinkedIn = LinkedIn || {};
LinkedIn = {
authTriggered: false,
authComplete: false,
authorise: function() {
IN.User.authorize(function() {
this.authComplete = true;
});
}
};
var authLink = document.getElementById('auth-link');
authLink.addEventListener('click', function(e) {
e.preventDefault();
LinkedIn.authTriggered = true;
LinkedIn.authorise();
});

Instead of IN.User.authorize() please use IN.UI.Authorize() as
var linkedin = IN.UI.Authorize().place();
linkedin.onWindowRemove.subscribe(function() {
// perform some action
});
thanks sanju for this answer
https://sanjutalks.wordpress.com/2017/10/04/linkedin-javascript-sdk-detecting-login-windows-close-event/

FB.logout() - no access token - "Log in as Different User"

This question is in relation to this question: FB.logout() called without an access token
I had a question i was hoping someone could help with.
I get everything in the link above, but how do you handle when someone uses a public computer and leaves themselves logged in to FB by accident? Then a new user tries to log in to an app, but it is not them. I want to have a button to log them out of FB altogether to "log in as a different user".
I cannot do that until they authorize the app, right? So they need to authorize the app under someone else's account and then log out? There has to be another way.
Any feedback would be great - tried searching for a while on this, but to no avail. I might be over thinking it, but there should be some way to "log in as a different user".

You can do something like:
FB.getLoginStatus(function(response) {
if (response.status === "connected") {
FB.api("me", function(response2) {
// notify the user he is logged in as response2.name, and if it's not him call FB.logout
}
}
else {
// prompt the user to login
}
}

Modify your logout to something like this :-
function logout(response){
console.log("From logout" + response);
if(!response.authResponse){
window.location = "/web/login/";
return;
}
FB.logout(function(response){
FB.Auth.setAuthResponse(null,'unknown');
logout();
});
}
i.e keep on sending logout request to Facebook till the actual logout happens.

Try to use Session and save the user's ID in that session.
You can control the expiration time of that session( by default its 20 minute if the user doesn't have any activity on the page)
then in each page Load even check whether the season is still active for that user or not.
page Load event:
if(Session["LoggedIn"]==null)
{
Response.Redirect("~/Login.aspx");
}
This code above will redirect user to login page of your website if the session has expired.

Simple example of popup authentication with Facebook Graph API

Trying to get Facebook to authenticate my users via a javascript popup. Right now, I have:
<input type="button" value="Connect with Facebook" onclick="window.open('https://graph.facebook.com/oauth/authorize?client_id=XXXXXXXXXXX&redirect_uri=http://example.com/step2&display=popup')" />
But when the user logs in via Facebook, the popup just displays the Facebook.com homepage. I'd like for the popup to authenticate the user and go away so that I can start retrieving user data from the graph api.
Is there a better / easier way to do this? Simple examples are appreciated.
Thank you.

oauth2 in facebook involves two steps, call authorize to get code, then call access_token to get token.
One way to deal with the pop login:
open login url in new window just like you did,when the facebook redirects back to your url in the popup, you set the cookie either through server side code or using javascript to capture url query parameter, when page is loaded in the popup, close the window immediately window.close.
On your main page, after your window.open code, add JavaScript code to detect if popup is closed and capture the cookie:
var signinWin;
$('#FacebookBtn').click(function () {
var pos = screenCenterPos(800, 500);
signinWin = window.open("[URL]", "SignIn", "width=780,height=410,toolbar=0,scrollbars=0,status=0,resizable=0,location=0,menuBar=0,left=" + pos.x + ",top=" + pos.y);
setTimeout(CheckLoginStatus, 2000);
signinWin.focus();
return false;
});
function CheckLoginStatus() {
if (signinWin.closed) {
$('#UserInfo').text($.cookie("some_cookie"));
}
else setTimeout(CheckLoginStatus, 1000);
}

Why not simply...
function authorizeAppInPopup() {
FB.login(function(response) {
if (response.authResponse) {
// User authorized app
} else {
// User cancelled login or did not fully authorize
}
}, {scope: 'publish_stream'});
}
??? : ]
https://developers.facebook.com/docs/reference/javascript/FB.login/

Checkout this article: Create Facebook PopUp Authentication Window using PHP and javascript for customize popup authentication.

It might be a good idea to do both a callback function from the Child window as Avner says as well as a timer that watches for the window to be closed. That way if the Child window is closed without a specific action you can take appropriate action on the Parent window.
**On Child**
// Set oAuthToken from server side when it comes back from authenticating
// and you have the token on the server side.
var oAuthToken = "";
oAuthToken = "--STRING INSERTED BY SERVER SIDE CODE--";
window.opener.pbFromPopup(oAuthToken);
**On Parent :**
function CheckLoginStatus() {
if (authWindow.closed) {
// Handle error if authentication window is closed
// without any action on Allow or Deny
alert("window closed");
//location.href = "errorPage.aspx?error=authwinclosed;
}
else setTimeout(CheckLoginStatus, 1000);
}
function pbFromPopup(token) {
// Function called from child window,
// token is passed back from child
authWindow.close();
// Put token in a hidden form field and submit the form to pass
// it back to the server
$("#authToken").val(token);
$("#form1").submit();
}

Facebook Connect Publish Stream JS Help

My site allow users to login via Facebook Connect and also allows them to update a status field our site. I want to include a checkbox below the status update field that will allow them to post this update to their Facebook profile as well if they so choose. In order to do this I need the user to grant our application permissions to post to their Facebook profile which is supported by prompting the user for 'publish_stream' permission using the JS function FB.Connect.showPermissionDialog http://developers.facebook.com/docs/?u=facebook.jslib.FB.Connect.showPermissionDialog.
The problem I'm having is figuring out if I need to prompt the user to do this. Basically the user experience I'd like to have is that when the user checks this box for the first time I want them to be prompted to grant this permission. Once that has been granted I won't need to prompt them in the future if they check that box again. I can't seem to figure out what JS to include in the onclick action of that checkbox that will check to see if the user has granted this permission and if not then prompt them, otherwise do nothing. Also after checking the box and granting the permission I want to do nothing (no page reload) but if they reject the request to grant permission I'd like the checkbox to be unchecked. I think I may need to use the FB.ApiClient.users_hasAppPermission JS function http://developers.facebook.com/docs/?u=facebook.jslib.FB.ApiClient.users_hasAppPermission but am still confused on what this would look like. The psuedo code for this would be:
onclick="
if(user_already_granted_permission) { do_nothing; }
else {
prompt_user_to_grant_permission {
wait_for_response_from_permission_dialog {
if(permission_granted) { do_nothing; }
else { uncheck_checkbox; }
}
}
}
"
One other thing worth noting is that I've already verified the user is logged in through Facebook Connect when the page was rendered. I'm hoping someone else using Facebook Connect has already been able to figure this one out. Thanks in advance for your help!

I recently developed an online demo that uses Facebook Connect and gets the friend list of a given user - it's not the same as your case, but I used FB.Facebook.apiClient.requireLogin to get the user logged, like this:
var api_key = 'd04fba62ff27c6c84a6b767d404bcec3';
var channel_path = '/xd_receiver.htm';
/* initialize facebook API */
FB_RequireFeatures(['Api'], function() {
FB.Facebook.init(api_key, channel_path);
var api = FB.Facebook.apiClient;
api.requireLogin(function(exception){
// user is logged in and my application
// has permissions to get friend list
});
});

You can do something like this:
FB.Facebook.apiClient.users_hasAppPermission('publish_stream', function(has_perms) {
if(has_perms) {
// User has granted the publish_stream permission
} else {
// User has not granted the publish_stream permission
}
});
The second param for the users_hasAppPermission function is a callback which returns the result of the check.