How to define array in js
To define a JavaScript array, you can use the following methods: Square brackets ([]) enclose element array literal syntax [1, 2, 3] new Array(3) constructor Array.of() method from Existing array creation spread operator (...)
How to define an array in JavaScript
Direct definition
The most direct way is to use square brackets ([]
) to enclose elements:
const myArray = ['apple', 'banana', 'orange'];
Array literal
You can also use a more concise array literal syntax:
const myArray = [1, 2, 3];
Keywordnew
Definition
You can also usenew
keywords and Array
constructors to define arrays:
const myArray = new Array(3); // 创建一个包含 3 个 undefined 元素的数组
Other methods
There are some other methods that can be defined Arrays, but they are less commonly used:
- Array.of() Method: Creates a new array containing the specified elements.
-
Create from existing array: A new array can be created from an existing array by copying or using the
slice()
method. -
Expand operator: Expand an iterable object (such as an array or collection) into an array by using the spread operator (
...
).
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