How can I send an array between different scopes?

Question

I created the array in the scope of $(document).ready(function(){});

for example:

$(document).ready(function(){
    $.getJSON("data.json", function(json) {

        function Question(q,correactA,array)
        {
            this.question=q;
            this.correct_a=correactA;
            this.answers=array;

        }

        multiQ= new Array();
        for (i=0;i<5;i++)
        {
            var q = json.questions[i].question;
            var corA= json.questions[i].correct_answer;
            var a = json.questions[i].answers;
            var aString = "";
            Object.keys(a).forEach(function (k) {aString += a[k] ;})
            multiQ[i]=new Question(q,corA,aString);
        }

        for (i=0;i<5;i++)
        {
            console.log(multiQ[i]);
        }

    });
});

Now I want to send the multiQ array to external var outside the scope. How can I do it?

*I created the array in the scope of* — No, you didn't. There is no `var` statement. It's a global already. — Quentin, Aug 09 '14 at 11:42
Possible duplicate of [Why is my variable unaltered after I modify it inside of a function? - Asynchronous code reference](http://stackoverflow.com/q/23667086/1048572) — Bergi, Aug 09 '14 at 11:49

joeltine · Answer 1 · 2014-08-09T11:48:58.117

-1

It's very ugly, but you could assign a global getter inside the document.ready. For example:

var multiQ = new Array();
window.getMultiQ = function() { return multiQ; }

Then outside of document ready, you could call "var q = getMultiQ();"

Again, this is very ugly and would lead to unmaintainable code very fast. Most likely, there's an easier/cleaner way to accomplish what you're trying to do.

edited Aug 09 '14 at 11:48

answered Aug 09 '14 at 11:41

joeltine

1,610
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23

For that, you should use a local `var multiQ` – Bergi Aug 09 '14 at 11:47
Oops, I just assumed he was using "var ..." and copy pasted. – joeltine Aug 09 '14 at 11:49

jimm101 · Accepted Answer · 2019-02-28T02:23:42.643

Declare

var multiQ= new Array();

outside $(document).ready function:

var multiQ= new Array();
$(document).ready(function(){
    $.getJSON("data.json", function(json) {

        function Question(q,correactA,array)
        {
            this.question=q;
            this.correct_a=correactA;
            this.answers=array;

        }

        for (i=0;i<5;i++)
        {
            var q = json.questions[i].question;
            var corA= json.questions[i].correct_answer;
            var a = json.questions[i].answers;
            var aString = "";
            Object.keys(a).forEach(function (k) {aString += a[k] ;})
            multiQ[i]=new Question(q,corA,aString);
        }

        for (i=0;i<5;i++)
        {
            console.log(multiQ[i]);
        }

      });
});

Yes, there's an asynchronous call, so each multiQ[i] won't be populated immediately. In the OP's code, it would be undefined until the callback, in the modification, it would be defined and have 0 length. — jimm101, Aug 11 '14 at 12:43

How can I send an array between different scopes?

2 Answers2