Although JavaScript is classless, we can still create an instantiate objects using a few different techniques. To demonstrate how to construct a JavaScript ‘class’, here are three examples below which are all essentially equivalent.

var test = new App();
var test2 = new App2();
var test3 = new App3();

Function object technique 1, returning an object containing function members.

function App() {
     // Constructor
     return {
          a : function(){
               console.log('a');
          },
          b : function(){
               console.log('b');
          }
     };
};

Function object technique 2, returning an object containing function members.

var App2 = function() {
     // Constructor
     return {
          a : function(){
               console.log('a');
          },
          b : function(){
               console.log('b');
          }
     };
};

Function object technique 3 using prototyping.

var App3 = function() {
     // Constructor
};

App3.prototype.a = function() {
     console.log('a');
};

App3.prototype.b = function() {
     console.log('b');
};

1. Ionut Popa on April 14th, 2009 at 3:03 pm

   If you need a singleton you can write something like this
   
var App4 = {
a: xxx,
b: function(){},
return{
b:b}