add array to js code example

Example 1: how to push items in array in javascript

let items = [1, 2, 3]
items.push(4); // items = [1, 2, 3, 4]

Example 2: add item to array javascript

const arr1 = [1,2,3]
const newValue = 4
const newData = [...arr1, obj] // [1,2,3,4]