Arrays

Create Array

const fruits = ["apple", "orange", "banana"];

// Different data types
const data = [1, "chicken", false];

Property .length

const numbers = [1, 2, 3, 4];

numbers.length; // 4

Index

// Accessing an array element
const myArray = [100, 200, 300];

console.log(myArray[0]); // 100
console.log(myArray[1]); // 200

Mutable chart

	add	remove	start	end
push	✔			✔
pop		✔		✔
unshift	✔		✔
shift		✔	✔

Array.push()

// Adding a single element:
const cart = ["apple", "orange"];
cart.push("pear");

// Adding multiple elements:
const numbers = [1, 2];
numbers.push(3, 4, 5);

Add items to the end and returns the new array length.

Array.pop()

const fruits = ["apple", "orange", "banana"];

const fruit = fruits.pop(); // 'banana'
console.log(fruits); // ["apple", "orange"]

Remove an item from the end and returns the removed item.

Array.shift()

let cats = ["Bob", "Willy", "Mini"];

cats.shift(); // ['Willy', 'Mini']

Remove an item from the beginning and returns the removed item.

Array.unshift()

let cats = ["Bob"];

// => ['Willy', 'Bob']
cats.unshift("Willy");

// => ['Puff', 'George', 'Willy', 'Bob']
cats.unshift("Puff", "George");

Add items to the beginning and returns the new array length.

Array.concat()

const numbers = [3, 2, 1];
const newFirstNumber = 4;

// => [ 4, 3, 2, 1 ]
[newFirstNumber].concat(numbers);

// => [ 3, 2, 1, 4 ]
numbers.concat(newFirstNumber);

If you want to avoid mutating your original array, you can use concat.

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