javascript arraymerge code example

Example 1: js join two arrays

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

Example 2: js combine two arrays

const letters = ['a', 'b', 'c'];
const numbers = [1, 2, 3];

letters.concat(numbers);
// result in ['a', 'b', 'c', 1, 2, 3]