What does array mean in js

Array object is an ordered collection used to store elements. When creating an Array, you can use an array literal or use [] to create an empty array. Access elements via the square bracket operator and use the push() and pop() methods to add and remove elements at the end respectively. JavaScript provides various array methods such as join() for converting strings, slice() for extracting subsets, sort() for sorting, and filter() for filtering elements.

Array in JavaScript

In JavaScript, an Array object represents an ordered collection of entities. It is an object whose elements can be accessed by index. Arrays are one of the most common object types in JavaScript.

Create Array

To create an array, you can use the following syntax:

<code class="js">const myArray = [];</code>

Another way to create an array is to use the literal syntax:

<code class="js">const myArray = [1, 2, 3];</code>

Accessing array elements

You can access elements in an array using the square bracket ([]) operator, followed by the index:

<code class="js">const myArray = [1, 2, 3];
console.log(myArray[1]); // 输出：2</code>

Add elements

You can use the push() method to add elements to the end of the array:

<code class="js">const myArray = [1, 2, 3];
myArray.push(4); // 添加 4 到数组末尾</code>

Delete elements

You can use pop() Methods to remove elements from the end of an array:

<code class="js">const myArray = [1, 2, 3];
myArray.pop(); // 从数组末尾删除 3</code>

Array methods

JavaScript contains a variety of array methods for performing common operations, such as:

• join() - Convert an array to a string
• slice() - Extract a subset of elements from an array
• sort() - Sort the elements in an array
• filter() - Filter elements from an array
• reduce() - Reduce elements in an array into a single value

Example

The following example demonstrates how to use the Array object:

<code class="js">const numbers = [1, 2, 3];

// 添加 4 到数组末尾
numbers.push(4);

// 将数组转换为字符串
const joinedNumbers = numbers.join(',');

// 对数组中的元素进行排序
numbers.sort();

// 筛选出偶数
const evenNumbers = numbers.filter((number) => number % 2 === 0);</code>

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