JSON - Beginning JavaScript - page 396

"age": 28,
"address": {
"numberAndStreet": "246 Someplace",
"city": "Somewhere",
"state": "Elsewhere"
}
}
]
This JSON array contains multiple objects that represent people and their addresses. The first is our
familiar John Doe, and the second is his little sister, Jane, who lives down the street. JSON data
structures can be as simple or complex as you need them to be.
serializing into Json
It's extremely easy to serialize JavaScript objects into JSON. JavaScript has an aptly named JSON
object that you use to parse JSON data and serialize JavaScript objects. All major browsers support
this JSON object. Older browsers, such as IE7 and below, can use Crockford's JSON implementation
( https://github.com/douglascrockford/JSON‐js ) to achieve the same results.
To serialize a JavaScript object into JSON, you use the JSON object's stringify() method. It accepts
any value, object, or array and serializes it into JSON. For example:
var person = {
firstName: "John",
lastName: "Doe",
age: 30
};
var json = JSON.stringify(person);
This code serializes the person object with JSON.stringify() and stores it in the json variable.
The resulting JSON‐formatted data looks like this:
{"firstName":"John","lastName":"Doe","age":30}
All unnecessary whitespace is removed, giving you an optimized payload that you can then send to
the web server or store elsewhere.
parsing Json
Parsing JSON into JavaScript objects is equally simple. The JSON object has a parse() method that
parses the JSON and returns the resulting object. Using the json variable from the previous code:
var johnDoe = JSON.parse(json);
This code parses the JSON text contained in json and stores the resulting object in the johnDoe
variable. And here's the wonderful thing—you can immediately use johnDoe and access its
properties, such as:
var fullName = johnDoe.firstName + " " + johnDoe.lastName;