Array

Creating and Initializing Arrays

const arr = [1,2,3]
const arr = Array.of(1,2,3)

Accessing Array Items

arr[index]

array is zero based (starts from 0)

Manipulating Arrays with methods

push()

add the values to the end of the array.

pop()

Removes the element from the end of the array.

shift()

Removes the element from the beginning of the array

unshift()

add the values to begining of the array

slice() and splice()

slice()

slice(begin, end)

Returns a shallow copy of a portion of an array into a new array object selected from begin to end (end not included)

splice()

splice(idx, deleteCount, newItems)

Changes the contents of an array by removing or replacing existing elements and/or adding new elements in place.

Array Searching and Looping

indexOf()

it has two bison

find()

Returns value of the first element in the provided array that satisfies the provided testing function

filter()

Creates a new array with all elements that pass the test implemented by the provided function

forEach()

executes a provided function once for each array element

Arrays in the DOM

document.getElementsByClassName()