how to insert an array into another array in javascript code example

Example 1: assign array to another array javascript

var ar = ["apple","banana","canaple"];
var bar = Array.from(ar);
alert(bar[1]); // alerts 'banana'

// Notes: this is for in In ES6, works for an object of arrays too!

Example 2: array insertion javascript

Array.prototype.insert = function ( index, item ) {
    this.splice( index, 0, item );
};

Example 3: add elements to an array with splice

var fruits = ["Banana", "Orange", "Apple", "Mango"];
document.getElementById("demo").innerHTML = fruits;

function myFunction() {
  fruits.splice(2, 0, "Lemon", "Kiwi");
  document.getElementById("demo").innerHTML = fruits;
}

Example 4: javascript push all elements of array to another array

var arrayA = [1, 2];
var arrayB = [3, 4];
var newArray = arrayA.concat(arrayB);