The Scenario:
You are working with a web service that returns JSON. You’ve used your javascript library to convert the string into a JSON object. Now you need to access the data in the object using javascript. Here are some examples:
JSON Property Types
The properties of a JSON object are going to be of the following types: another Object or an Array of Objects. Objects are name – value pairs. The value that is returned can be a string, a number, another object, an array, true, false, or null.
Accessing an Object type in JSON:
//A Simple Example:
// Your JSON object(yourData) has a name property,
// you could get it this way:
var name = yourData.Name;
// alternatively you can use a string index:
var name = yourData["Name"];
//A Nested Example
// Your JSON object(yourData) has a Books object
// with nested Book objects
var books = yourData.Books;
for (var x in books)
{
var book = books[x];
var title = book.title;
}
Accessing an Array type in JSON:
//A Nested Example with an Array
// Your JSON object(yourData) has a
// Books array with nested Book objects
var books = yourData.Books;
for (var x = 0; x++; x< books.length)
{
var book = books[x];
var title = book.title;
}
Getting Property Names
// When you want to know the name of the
// properties of an object you can iterate
// through the object using for - in loop
var books = yourData.Books;
for (var x in books)
{
alert(x);
}


Fri, Jun 26, 2009
Tech Tips