My webzone

A place for John Bintz to ramble.

JavaScript in my jQuery: Objects as data containers

Sometimes you have to pass in options to jQuery functions like this:

  height: '300px',
  opacity: 0.75,


  height: '300px',
  opacity: 0.75

is the most basic form of an Object. Objects have two things: properties and methods. When you attach other things to an object, like the String 300px or the Number 0.75, you’re creating properties.

Methods are Functions attached to an object. When you extend jQuery.fn with your own jQuery actions, you’re creating a new method:

$.fn.makeAllTranslucent = function() {
    height: '300px',
    opacity: 0.75

  return this;

// now you have a shortcut!

You can add and change properties on an object after-the-fact, too:

var properties = { height: "300px" };
if confirm("Want them translucent?") {
  properties.opacity = 0.75;

// pass the object in as the first parameter

Because of the way JavaScript is designed, everything is an object: the one you created with {curly: 'brackets'}, $.fn, standalone Functions, everything. This lets developers do some very clever things with JavaScript.