Languages
[Edit]
EN

JavaScript - how to insert element to array?

10 points
Created by:
JustMike
3488

In JavaScript it is not intuitive at first time how to insert element to array into some index position. Insert element into some index position operation can be achieved with Array.prototype.splice method. This article is focused on how to do it.

1. Insert element into some index position with Array.prototype.splice method example

//  index:    0    1    2    3
var array = ['a', 'b', 'c', 'd'];

// inserting 'new item' element into 1st index position
array.splice(1, 0, 'new item');

console.log(array);

Output:

[ 'a', 'new item', 'b', 'c', 'd' ]

Notes about Array.prototype.splice method:

  • takes as first argument index into 1st index position
  • takes as second argument number of removed elements - in this case we do not remove elements
  • takes as third argument added element

Refrences

  1. Array.prototype.splice method - MDN Docs 

Hey 👋
Would you like to know what we do?
  • Dirask is a friendly IT community for learners, professionals and hobbyists to share their knowledge and help each other in extraordinary easy way.
  • We welcome everyone,
    no matter what the experience,
    no matter how basic the question is,
    this community will help you.