JAVASCRIPT

How to Copy an Array With the Spread Operator in JavaScript

let studentNames = ["Daniel", "Jane", "Joe"];

let names = [...studentNames];

console.log(names); // ["Daniel","Jane","Joe"]

// This saves us the time we would use to write a loop statement:

Clone Array Using Spread Operator

let arr1 = [ 1, 2, 3];
let arr2 = arr1;

console.log(arr1); // [1, 2, 3]
console.log(arr2); // [1, 2, 3]

// append an item to the array
arr1.push(4);

console.log(arr1); // [1, 2, 3, 4]
console.log(arr2); // [1, 2, 3, 4]

copy an array with the spread operator

const arr1 = ['JAN', 'FEB', 'MAR', 'APR', 'MAY'];
let arr2;

arr2 = [...arr1];

console.log(arr2); // ['JAN', 'FEB', 'MAR', 'APR', 'MAY'];

Copy Array Using Spread Operator

const arr1 = ['one', 'two'];
const arr2 = [...arr1, 'three', 'four', 'five'];

console.log(arr2); 
//  Output:
//  ["one", "two", "three", "four", "five"]

copying arrays in javascript without reference | copying arrays using spread operator

let arr1 = [1,2,3,4,5];
let arr2 = [...arr1];
arr2[0] = -2;
console.log(arr2);// outputs : [-2,2,3,4,5]
console.log(arr1);// outputs : [1,2,3,4,5]