concat 2 array javascript code example

Example 1: combine two arrays javascript

let arr1 = [0, 1, 2];
let arr2 = [3, 5, 7];
let primes = arr1.concat(arr2);

// > [0, 1, 2, 3, 5, 7]

Example 2: javascript merge array

// ES5 version use Array.concat:
let array1 = ["a", "b"]
let array2 = ["1", "2"]
let combinedArray = array1.concat(array2);
// combinedArray == ["a", "b", "1", "2"]

// ES6 version use destructuring:
let array1 = ["a", "b"]
let array2 = ["1", "2"]
let combinedArray = [...array1, ...array2]
// combinedArray == ["a", "b", "1", "2"]

Example 3: js join two arrays

[1,2,3].concat([4,5,6])
// [1,2,3,4,5,6]

Example 4: join two arrays javascript

// using push and apply to return the same array
const arr1 = ['a', 'b'];
const arr2 = ['c', 'd'];
arr1.push.apply(arr1, arr2);
console.log(arr1) // ['a', 'b', 'c', 'd']