Call variables from one javascript file to another

Question

How can I call the variables that I stored in one javascript file from another?

var.js

var VAR = new Object;
VAR.myvalue = "Yeah!";

then I want to use VAR.myvalue here

sample.js

alert(VAR.myvalue);

Answer 1

First, instead of

var VAR = new Object;
VAR.myvalue = "Yeah!";

Opt for

var VAR = {
    myvalue: "Yeah!"
 };

But so long as var.js is referenced first , before sample.js, what you have should work fine.

var.js will declare, and initialize VAR, which will be read from the script declared in sample.js

Answer 2

Include both JavaScript file in one HTML file, place sample.js after var.js so that VAR.myvalue is valid:

<script type="text/javascript" src="var.js"></script>
<script type="text/javascript" src="sample.js"></script>

Answer 3

Try separating your scope using a module pattern . This will eliminate headaches in the future.

var.js

var someVar = (function () {
  var total = 10; // Local scope, protected from global namespace

  return {
    add: function(num){
      total += num;
    }
  , sub: function(num){
      total -= num;
    }
  , total: function(){
      return total;
    }
  };
}());

Then you can use that object's methods and properties from anywhere else.

sample.js

someVar.add(5);
someVar.sub(6);
alert(someVar.total());