Introduction to JavaScript Array Methods

Push Method in Arrays

const k = [1,2,3,4,5,6]
k.push(7);
console.log(k);

Output

[1, 2, 3, 4, 5, 6, 7]

Pop Method in Arrays

const k = [1,2,3,4,5,6]
k.pop()
console.log(k);

Output

[1, 2, 3, 4, 5]

indexOf method in Arrays

const k = [1,2,3,4,5,6]
  console.log(k.indexOf(3));

Output

2

lastIndexOf method in Arrays

const k = [1,2,3,4,5,6]
let x = k.lastIndexOf(6)
console.log(x);

Output

5

Finding length of an Array

const k = [1,2,3,4,5,6]
let x = k.length
console.log(x);

Output

6

reverse method in Arrays

const k = [1,2,3,4,5,6]
k.reverse()
console.log(k);

Output

[6, 5, 4, 3, 2, 1]

shift method in Arrays

const k = [1,2,3,4,5,6]
let x = k.shift()
console.log(x);

Output

1

slice method in Arrays

const k = [1,2,3,4,5,6]
        const j = k.slice(1,3)
        console.log(j);

Output

[2, 3]


//only starting index for slice
const k = [1,2,4,3,5,6]
console.log(k.slice(1));//will slice from index 2 to 6

Output

[2, 4, 3, 5, 6]

sort method in Arrays

const k = [1,2,4,3,5,6]
          k.sort()
          console.log(k);

Output

[1, 2, 3, 4, 5, 6]

splice method in Arrays

const k = [1,2,4,3,5,6]
k.splice(2,2) //removes 2 elements from index 2
console.log(k);

Output

[1, 2, 5, 6]

//0 here represents remove none
const k = [1,2,4,3,5,6]
k.splice(2,0,88,99) //add two elements at index 2
console.log(k);

Output

[1, 2, 88, 99, 4, 3, 5, 6]

//splice for add and remove elements 
//remove 2 elements and add two elements at index 2
const k = [1,2,4,3,5,6]
k.splice(2,2,88,99) //removes 2 elements and adds two elements at index 2
console.log(k);

Output

[1, 2, 88, 99, 5, 6]

toString method in Arrays

const k = [1,2,4,3,5,6]
console.log(k.toString());
console.log(k.length);

Output

6