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);
}

Here they are:

My JSON Editor with Demo
I like this one because it is simple and easy to use. You paste in your json string, click save and it gives you a quick tree view of your object.

My JSON Editor

JSON Editor
This one works too.

JSON Editor

Firebug JSON Explorer
I actually havn’t it tried this one, but it was definitely worth mentioning. I use Firebug but this feature is only available in the 1.4 beta. I wasn’t feeling brave enough to upgrade my Firebug version at the time of writing.

What would be nice to see…
I would want to click on an element in the tree view and get the fully qualified javascript code to read the value. Save me some typing.