insert value at beginning of array javascript code example

Example 1: javascript add new array element to start of array

var colors = ["white","blue"];
colors.unshift("red"); //add red to beginning of colors
// colors = ["red","white","blue"]

Example 2: array.unshift in javascript

//The unshift() method adds one or more elements to the beginning of an array 
//and returns the new length of the array.

const array1 = [1, 2, 3];
console.log(array1.unshift(4, 5));
// expected output: 5
console.log(array1);
// expected output: Array [4, 5, 1, 2, 3]