Page 86 - JavaScript

Chapter 6: Arrays

Syntax

• array = [value, value, ...]
• array = new Array(value, value, ...)
• array = Array.of(value, value, ...)
• array = Array.from(arrayLike)

Remarks

Summary: Arrays in JavaScript are, quite simply, modified Object instances with an advanced
prototype, capable of performing a variety of list-related tasks. They were added in ECMAScript
1st Edition, and other prototype methods arrived in ECMAScript 5.1 Edition.

Warning: If a numeric parameter called n is specified in the new Array() constructor, then it will
declare an array with n amount of elements, not declare an array with 1 element with the value of
n!

console.log(new Array(53)); // This array has 53 'undefined' elements!

That being said, you should always use [] when declaring an array:

console.log([53]); // Much better!

Examples

Standard array initialization

There are many ways to create arrays. The most common are to use array literals, or the Array
constructor:

var arr = [1, 2, 3, 4];
var arr2 = new Array(1, 2, 3, 4);

If the Array constructor is used with no arguments, an empty array is created.

var arr3 = new Array();

results in:

[]

Note that if it's used with exactly one argument and that argument is a number, an array of that

https://riptutorial.com/ 43