JavaScript and JQuery

JavaScript (/ECMAScript): http://en.wikipedia.org/wiki/JavaScript

JavaScript is an in-browser programming language designed to provide customization of interactive behavior and reduce real or apparent user-interface latency (e.g. avoid up-front server round trips – see AJAX, below).

JavaScript examples

Dynamically creating text in a variety of ways:

https://github.com/ctb/cse491-serverz/tree/day16/js-examples/ex1.html

https://github.com/ctb/cse491-serverz/tree/day16/js-examples/ex2.html

https://github.com/ctb/cse491-serverz/tree/day16/js-examples/ex3.html (and https://github.com/ctb/cse491-serverz/tree/day16/js-examples/hello.js)

https://github.com/ctb/cse491-serverz/tree/day16/js-examples/ex4.html

Interaction with the user:

https://github.com/ctb/cse491-serverz/tree/day16/js-examples/ex5.html

Interaction with forms:

https://github.com/ctb/cse491-serverz/tree/day16/js-examples/ex6.html

Variables and oddities:

https://github.com/ctb/cse491-serverz/tree/day16/js-examples/ex7.html

Object oriented programming:

https://github.com/ctb/cse491-serverz/tree/day16/js-examples/ex8.html

Modifying the current page’s title through Document Object Model access:

https://github.com/ctb/cse491-serverz/tree/day16/js-examples/ex9.html

JQuery examples

Since JavaScript is one of the worst possible languages actually in wide use (it’s needlessly inconsistent and largely incoherent) a number of frameworks have popped into existence to help programmers actually make effective use of it.

JQuery (http://jquery.org/) is one such framework; it’s relatively small, fast, and concise.

JQuery uses two nice basic concepts: selectors, and chaining. Selectors let you pick out sets or subsets of elements based on CSS-style patterns:

https://github.com/ctb/cse491-serverz/tree/day16/jquery-examples/ex1.html

Chaining lets you apply multiple functions in sequence without respecifying which elements you want to modify:

https://github.com/ctb/cse491-serverz/tree/day16/jquery-examples/ex2.html

You can specify all sorts of fun tricks:

https://github.com/ctb/cse491-serverz/tree/day16/jquery-examples/ex3.html