Prototype vs jQuery

To and from JavaScript libraries by Remy Sharp

(Adapted S9 Version from Original PDF Slide Deck)

Why Prototype?

  • Extends the DOM and core JavaScript objects
  • An arsenal of utility functions

Based on Prototype 1.5.1 & 1.6

Why jQuery

  • Centred around chaining and binding methods to objects and elements
  • Totally encapsulated
  • Aims to be exceptionally easy to develop with

Based on jQuery 1.2.1

Differences in Native Support

Prototype has:

  • Class creation
  • Try.these
  • Position, Range

jQuery has:

  • No Conflict ($)
  • Effects

Non-exhaustive list, and in most case, the functionality can be implemented with plugins.

Syntax Comparison

  • Dollar ($) Variable
  • CSS Based Selectors
  • DOM Ready Event
  • Iteration
  • DOM Walking
  • DOM Manipulation
  • Element Classes
  • Events
  • Bubbling
  • Ajax
  • Plugins / Extensions
  • Browser Detection

Dollar Variable

  • Prototype uses $ for id based selection
  • jQuery $ = CSS based selector (= $$ in Prototype)

Note that Prototype will return element objects or arrays of elements for most methods. jQuery will usually return a jQuery object (which looks like an array in Firebug).

$ Example





CSS Based Selectors

  • Prototype – $$

To narrow down it’s context use Element.getElementsBySelector(selector) (or in 1.6)

  • jQuery – $

Virtually all of jQuery’s DOM selection is done using CSS 1-3

Selector Examples




// 1.6




DOM Ready Event

  • Prototype – uses Event object
  • jQuery – uses two types of syntax, both meaning the same thing

jQuery uses different methods to execute the ready function when the DOM is ready, using specific methods for Internet Explorer and for Safari1

1 window.onload again, The window.onload Problem Revisited

Ready Example



Prototype 1.6



 // or


Prototype – current active element, and position is passed in to callback function.

[el1, el2].each(fn(el, i))

jQuery – current element position passed in to callback function, and binds the function to current active element (i.e. this is set to the active element).

$([el1, el2]).each(fn(i))

DOM Walking

Prototype – up, down, next & previous

jQuery – parent/s, children, next, prev (& nextAll, prevAll)

DOM Manipulation

Prototype – Insertion class: After, Before, Bottom, Top, update (1.6 will add: Element.insert)

jQuery – after, before, append, prepend & html

Element Classes

Prototype – addClassName, removeClassName, toggleClassName, hasClassName

jQuery – addClass, removeClass, toggleClass, is (for class matching)


Prototype – Event class: observe, stopObserving (Prototype 1.6 will support Element.observe)

jQuery – bind, unbind (also supports shortcuts: .click, .dblclick, .mouse*, .ready, .focus, .blur)


Prototype – Event.stop()

jQuery – return false or event.stopPropagation() (event is passed in to the callback)



new Ajax.Request(url[, options])


$.ajax(options) // url included in options

Ajax – Method Comparison

Prototype jQuery
onCreate beforeSend
onSuccess success
onException error
onComplete complete

Ajax Examples


new Ajax.Request('/profile', {
  method: 'post',
  onSuccess: function (j) {
    // do stuff with response


$.ajax({ url: '/profile',
  data: {'action':'check_username','username': $('#username').val()},
  type: 'post',
  success: function (json) {
    // do stuff with response

Plugins / Extensions


Element.addMethods({myPlugin : function(element, args) { return element; }});


jQuery.fn.myPlugin = function (args) { return this; };

Browser Detection

Prototype – Prototype.Browser.IE, .Webkit, etc.

jQuery – jQuery.browser.msie, .safari, etc.