concat method in js code example

Example 1: javascript append to array

var colors=["red","white"];
colors.push("blue");//append 'blue' to colors

Example 2: javascript concat two arrays

//ES6
const array3 = [...array1, ...array2];

Example 3: javascript concat

let chocholates = ['Mars', 'BarOne', 'Tex'];
let chips = ['Doritos', 'Lays', 'Simba'];
let sweets = ['JellyTots'];

let snacks = [];
snacks.concat(chocholates);
// snacks will now be ['Mars', 'BarOne', 'Tex']
// Similarly if we left the snacks array empty and used the following
snacks.concat(chocolates, chips, sweets);
//This would return the snacks array with all other arrays combined together
// ['Mars', 'BarOne', 'Tex', 'Doritos', 'Lays', 'Simba', 'JellyTots']

Example 4: concatenate multiple arrays javascript

const array1 = ['a', 'b', 'c'];
const array2 = ['d', 'e', 'f'];
const array3 = [...array1, ...array2];

console.log(array3);
// expected output: Array ["a", "b", "c", "d", "e", "f"]

Example 5: how the concat function works javascript

var arr = [1, 2, 3, 4];
var arr2 = [5, 6, 7, 8];

const both = arr.concat(arr2);

console.log(both);
//[1, 2, 3, 4, 5, 6, 7, 8]