Set Global Array/Variable from inside a Javascript Function

Hi Experts,

Is there some big secret to setting array or variable values within a function for global access?

I'm using jQuery's getJSON()  to return rows from our database. I then loop through and format the values there-in for display. my problem is I need to access this information later in the script.

I've omitted the var keyword before declaring the value and tested window.string to no avail

How can I achieve global scope for an array or indeed variable from within a function?

Thank you
LVL 4
wilson1000Asked:
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BardobraveConnect With a Mentor Commented:
If you declare a variable in the global scope of a page, it will be available to all the page.

Scopes in javascript code are hyerarchical, so when something is defined in a scope, it's available in all children scopes, but not in ancestor's ones.

Your biggest problem here would be if you have your variable defined in a js file and you want to access it from another one, as to my experience different files means completely different scopes although they are loaded in the same page.

To solve this type of problems, you can use hidden inputs in page code to store values and be able to retrieve them from any code point that executes on the same page.

Hope it helps.
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Shinesh PremrajanEngineering ManagerCommented:
Have you tried with the closures in javascript, I think the answer lies there, in a closure the variable willl be available even after the function exit.

Hope this helps
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imaki06Commented:
You should declare that variable outside of the function.

Like:

<script type="javascript">
var myarr=new Array();

function myfunc(){
  myarr[0]="first";
}
</script>
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wilson1000Author Commented:
Thank you shinuq, would you clarify what a closure is please?
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ProculopsisConnect With a Mentor Commented:

//This should be available globally

   window.myArray = ["Hello","World"]
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BadotzConnect With a Mentor Commented:
Very Bad to pollute the window object in such a way.

Current practice is to declare a namespace for your stuff, keeping things separate from your libraries, etc.:

var G = {
    "ra" : [ "a", 1, "b", 2, "c", 3 ],
    "c123" : 123,
    "etc" : "etc."
}

and then retreive them as needed:

function something() {
    var cra = G.ra; // Get common array
    G.ra = [ "x", 24, "y", 25, "z", 26 ]; // Change common array
}
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ProculopsisCommented:

Just for clarification, this is a perfectly acceptable solution:

 window.myArray = ["Hello","World"]

...perhaps it is not clearly understood that, at the outermost level, vars are actually members of the window object and do not cause polution.  You can check this for yourself with the following statements: var G = "!"; alert( window.G );
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BadotzCommented:
We will have to agree to disagree on that point.
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BadotzCommented:
No worries - glad to help.
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