copy an array in javascript code example

Example 1: javascript copy an array

let arr =["a","b","c"];
// ES6 way
const copy = [...arr];

// older method
const copy = Array.from(arr);

Example 2: javascript copy array

var numbers = [1,2,3,4,5];
var newNumbers = Object.assign([], numbers);

Example 3: javascript copy array

/* Copying arrays or parts of arrays in JavaScript */

var fruit = ["apple", "banana", "fig"]; // Define initial array.
console.log(fruit); // ["apple", "banana", "fig"]

// Copy an entire array using .slice()
var fruit2 = fruit.slice(); 
console.log(fruit2); // ["apple", "banana", "fig"]

// Copy only two array indicies rather than all three
// From index 0 (inclusive) to index 2 (noninclusive)
var fruit3 = fruit.slice(0,2); 
console.log(fruit3); // ["apple", "banana"]

Example 4: javascript copy array

// this is for array with complex object
var countries = [
  {name: 'USA', population: '300M'}, 
  {name: 'China', population: '1.6B'}
];

var newCountries = JSON.parse(JSON.stringify(countries));