I'll be honest, I don't write a lot of object oriented Javascript code. It seems like every time I do, I have to look up how to do it correctly and there are lots of different ways to write object oriented code in javascript. I found a Nefarious Designs article to be a good reference.
Many people suggestion using prototype to add functions to an object, but that seems less like other languages, so I prefer the following style.
Whenever you think about using a global variable or trying to pass something by reference, it might be time to setup an object.
Note: In Javascript, objects are passed by reference while strings and integers are not.
function circle(radius) { var radius = radius; var getArea = function() { return (this.radius * this.radius) * Math.PI; }; return true; }
Here's another way. I'm not sure which I prefer.
function circle(radius) { this.radius = radius; this.getArea = function() { return (this.radius * this.radius) * Math.PI; }; return true; }