Head Rush Ajax

378

Chapter 7

JSON is just JavaScript

So JSON is just JavaScript, right? I don’t

need to worry about the DOM, or some

toolkit... I can just use JSON in my code

sort of like I’d use an array.

JSON is just a way to represent objects

in JavaScript. In other words, JSON

is JavaScript. You don’t need to work

with the Document Object Model, or

any other toolkit, to use JSON in your

JavaScript code.

In fact, you can work with data that’s a

lot trickier than the simple set of values

you’ve seen so far... let’s see how Katie

and Boards ‘R’ Us can break their sales

data down a little further...

JSON is

JavaScript.

json is javascript

you’re on your way �

379

xml versus json

{“totals”: [

{“location”:“Vail”, “boardsSold”:642, “bootsSold”:86, “bindingsSold”:19},

{“location”:“Santa Fe”, “boardsSold”:236, “bootsSold”:45, “bindingsSold”:32},

{“location”:“Boulder”, “boardsSold”:453, “bootsSold”:90, “bindingsSold”:16},

{“location”:“Denver”, “boardsSold”:379, “bootsSold”:94, “bindingsSold”:18}

]};

Here’s a little more JSON.

This time, the Boards ‘R’ Us

sales are broken up by city.

// Get the updated totals from the JSON response

var jsonData = eval(‘(‘ + request.responseText + ‘)’);

var totalBoards = jsonData.totals[0].boardsSold +

jsonData.totals[1].boardsSold +

jsonData.totals[2].boardsSo ...