How much data can a javascript global variable hold??

Question

Hi,

To enable a go back function with an ajax div i have create these simple functions and i was wondering how much data a .js global variable can hold??

    var dataAfterSearch; //global variable which holds our search results

function goBackAfterSearch() {
    /**
    *   function which displays the previous state
    *
    **/
    $.ajaxSetup ({
        cache: false
    });
    //alert("Previous Search" +dataAfterSearch);
    $('#result').html(dataAfterSearch);
     paginateIt();
}
function setDataAfterSearch(data)
{   
    /**
    * function to set the global dataAfterSearch
    *
    **/
    dataAfterSearch = data;
}

kind regards

Answer 1

Global variables aren't any different than non-global variables in what and how much they can hold. The specifications don't mention a limitation on string length (a string being what will be returned by AJAX), so I think it's implementation dependent.

I found this discussion on bytes.com where they mention some limitations they reached amongst different browsers.

Answer 2

a variable in javascript can hold an object or a string. An object is an unlimited data structure. Strings are limited only by the implementation (as Bob said), and shouldn't be a constraint for you.

Answer 3

There is no limit, the maximum size is browser/implementation specific.

You can test the limit by executing a script like this:

var str = "";
var sizeCount = 0;
while( true ) {
   str += "a";
   if( ++sizeCount >= 1048576 ) { // Show an alert for every MB
      alert( str.length );
      sizeCount = 0;
   }
}

I get an error in Chrome around 26MB.