Quickstart Javascript

Thursday, September 10, 2015

Javascript Quickstart

Javascript Rocks


  1. Javascript is not Java
  2. Similar names for marketing reasons
  3. Developed by Netscape in 1995 to create products and applications in the browser
  4. It's primarily client side
  5. Originally designed as a scripting language, it is actually a fully featured language

What can we do with it:

  1. Small enhancements such as infinite scrolling
  2. Parallax effects in the browser
  3. Build games with Javascript
  4. For the internet of things, robots, wearable tech and more
  5. Build full application, youtube application for playstation built with AngularJS

Hello World in Javascript

Use confirm function for confirm message box

Prompt allows the user to enter a value in message box

Some common operators

Echoing out a warning using the warn function

Use the error function on the console to log errors

Primitive data types

Variables, variable keyword is var

Control flow, if/else statements

Using else if

Basic fizzbuzz version between 0 and 5

Basic text game

Switch case statement example

Switch case with user input

For loops

More complex fizzbuzz version

While loops, do while always runs at least once

While loop example

Functions for readability and refactoring

More on functions

Arrays have a zero based index

Looping over an array

Text adventure game enhanced with some new features



Object literals

Object constructors are templates for creating objects

This and the global object, window dot works on our code because all objects are added to the global window object

Global scope, global variable, accessible from everywhere in the code

Local scope, variable declared inside function is a local variable

Variable declared without var is global variable

Understanding scope

Inner function has access to code in outer function

Outer function doesn't have access to inner function

Use JsLint to enforce a coding convention a good standard, it defines a professional subset of javascript

Get, set and delete

Object literals is an expressive notation for creating objects

Function of new prefix operator

There is only one number type in Javascript

Number methods add a method trunc to number prototype

Default Success Warning Important Info Inverse
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