This document provides an introduction to JavaScript and its key concepts. It discusses why JavaScript is useful, highlighting features like closures and functions being first-class citizens that give JavaScript power and speed. It then covers basic variable types in JavaScript like numbers, objects, arrays and strings. Examples are given of declaring variables of different types. The document also demonstrates how to work with objects and functions in JavaScript, including higher-order functions and intervals. The overall goal is to help understand basic JavaScript syntax and functionality.
4. Goal of lesson
●
Understand:
function Person (name) {
this.name = name;
}
Person.prototype.getName = function () {
return this.name;
}
●
Wow very function
5.
6. So variables in JavaScript
●
Variables are declared:
var doge = 'doge';
●
Data types:
1. Number
2. Object
3. Array
4. Strings
5. Booleans
7. Much examples
var dog = 'doge';
var dog = {name: 'doge'};
var dog = ['dog'];
var isDoge = true;
var numDoge = 1; //only one doge!
8.
9. Wow Objects
var person = {name: 'Bill',
age: 33};
console.log(person.name) //'Bill'
console.log(person.age) //33
10. Much Functions
function doFizzBuzz (range) {
var i = 0,
toReturn = '';
for (i = 0; i < range; i++) {
if (i % 3 === 0) {
toReturn += 'Fizz';
}
if (i % 5 === 0) {
toReturn += 'Buzz';
}
toReturn += 'n';
}
return toReturn;
}
12. Much idiomatic
function doFizzBuzz (range) {
var i = 0;
for (i = 0; i < range; i++) {
if (i % 3 === 0) {
this.result += 'Fizz';
}
if (i % 5 === 0) {
this.result += 'Buzz';
}
this.result += 'n';
}
}
13. Much high order function
//interval stores the id of this interval
var interval = window.setInterval(function () {
if (this.isVisible === true) {
document.getElementById('change').style.visibility = 'hidden';
this.isVisible = false;
} else {
document.getElementById('change').style.visibility = 'visible';
this.isVisible = true;
}
}, 500);
