Javascript Function and show global vars

Question

I try do this :

<script>
    FB.getLoginStatus(function(response) {  
        if (response.status==='connected') {
            var fb_status="on";
        } else {
            var fb_status="off";    
        }
    });

    alert("ok"+fb_status);

</script>

If i put alert inside function , this alert works , by other side , if i put this alert outside , no works

i supose this it´s more or less the same as global vars in php but no have many experience in Javascript

I only need the same i put in the example for detect in a var the result from function but as in the case i put as example , outside function , i try many things but no get results

Regards and thank´s for the help to community

declare the fb_status variable outside the block and assign required "on" & "Off" inside the block. — Ramkumar, Apr 30 '15 at 10:32
You are ordering a pizza then trying to eat it before it is delivered! — iCollect.it Ltd, Apr 30 '15 at 10:33
In this case, U can use callback function. Please try this link, which answer ur question, http://stackoverflow.com/questions/7522947/fb-getloginstatus-does-not-fires-callback-function — Ramkumar, Apr 30 '15 at 10:51

score 0 · Answer 1 · answered Apr 30 '15 at 10:33

0

FB.getLoginStatus is async function so when you try getting fb_status outside it, you get undefined because FB.getLoginStatus didn't return any result yet

answered Apr 30 '15 at 10:33

Pavel Komiagin

708
6
10

Yes, this is why it fails, but what is the *answer* to the question? – iCollect.it Ltd Apr 30 '15 at 10:35
Yes really i need get result of this outside function and with this i can run other functions but no experience in this cases ....... – Miguel Garcia Apr 30 '15 at 10:37
@Miguel Garcia: Due to the timing issue, you cannot just use a global variable. You need to restructure your code,. Can you show the rest of your example? – iCollect.it Ltd Apr 30 '15 at 10:40

score 0 · Answer 2 · answered Apr 30 '15 at 10:35

As the FB.getLoginStatus call is asynchronous, the result only occurs later and is only relevant inside the event handler:

e.g.

<script>
    FB.getLoginStatus(function(response) 
    {   
        // This line gets called many millisconds later
        console.log("When I have a status");
        if (response.status==='connected') 
        {
           var fb_status="on";
        }
        else
        {
            var fb_status="off";    
         }
         alert("ok"+fb_status);
    });
    // This line executes long before the callback returns
    console.log("After call");
</script>

Check out the console to see the order of events:

"After call"
"When I have a status"

You mention in comments you want to use the value elsewhere. The problem will be the timing as the result you want will only occur later.

Javascript Function and show global vars

2 Answers2