What is array-like object in JavaScript

An array-like object in JavaScript is an object that has numeric indices and a length property but does not necessarily inherit from the Array prototype.

While these objects resemble arrays in terms of their structure (indexed elements with a length property), they lack many of the built-in methods and functionalities provided by true arrays such as forEach, map, filter, and others.

To work with array-like objects, you can either use a for loop to iterate over their elements, or convert them to real arrays using methods like Array.from() or the spread operator.

let arrayLikeObject = {
  0: 'apple',
  1: 'banana',
  2: 'orange',
  length: 3

let realArray = Array.from(arrayLikeObject);
console.log(realArray); // ['apple', 'banana', 'orange']

Common examples of array-like objects in JavaScript include the arguments object inside functions, the NodeList returned by DOM queries, and the result of certain API calls.