concatenation of array js code example

Example 1: js join two arrays

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

Example 2: combine 2 arrays javascript

//ES6 using the spread operator
const itemsA = [ 'Lightsaber', 'Mockingjay pin', 'Box of chocolates' ];
const itemsB = [ 'Ghost trap', 'The One Ring', 'DeLorean' ]
const allItems = [ ...itemsA, ...itemsB ];