In the previous article, we learned how to use includes() to determine whether an array contains a specified value. Please see "How to use includes() in js to determine whether an array contains a specified value". This time we will take a look at how to create an array with a variable number. You can refer to it if you need it.
Do you still remember that the editor introduced How to create an array object? If you don’t remember or don’t know, you can click on the text to view it.
Previously we introduced how to create an array object through array. Today we are going to create a variable-length array, so we can no longer use array to create it. So what do we need to use to create it?
First let’s look at a small example.
var arr = new Array(7); arr[0] = "one"; arr[1] = "two"; arr[2] = "three"; arr[3] = "one"; arr[4] = "two"; console.log(arr);
This is the array object created through array before. The result is
Let’s take a look at the array created through array.of.
var nums=new Array.of(7); console.log(nums);
The result of this is
You can see the difference right now.
Although they are both 7, the 7 in array represents the length of the array, while the 7 in Array.of represents creating an array with a single element 7.
Having said so much, let us take a look at this method in detail.
The Array.of() method creates a new array instance with a variable number of arguments, regardless of the number or type of arguments. The difference between Array.of() and Array constructors is the handling of integer arguments: Array.of(7) creates an array with a single element 7 , while Array(7) creates an empty array of length 7 (note: this refers to an array with 7 empty positions (empty), not an array composed of 7 undefined).
Let’s take a look at the syntax format of this method.
Array.of(任意个参数)
The parameters of this method can be any number, and these parameters will become the elements in the returned array in order.
That’s all. If you need it, you can read: javascript advanced tutorial
The above is the detailed content of How to create an array with variable number in js. For more information, please follow other related articles on the PHP Chinese website!

去掉重复并排序的方法:1、使用“Array.from(new Set(arr))”或者“[…new Set(arr)]”语句,去掉数组中的重复元素,返回去重后的新数组;2、利用sort()对去重数组进行排序,语法“去重数组.sort()”。

本篇文章给大家带来了关于JavaScript的相关知识,其中主要介绍了关于Symbol类型、隐藏属性及全局注册表的相关问题,包括了Symbol类型的描述、Symbol不会隐式转字符串等问题,下面一起来看一下,希望对大家有帮助。

怎么制作文字轮播与图片轮播?大家第一想到的是不是利用js,其实利用纯CSS也能实现文字轮播与图片轮播,下面来看看实现方法,希望对大家有所帮助!

本篇文章给大家带来了关于JavaScript的相关知识,其中主要介绍了关于对象的构造函数和new操作符,构造函数是所有对象的成员方法中,最早被调用的那个,下面一起来看一下吧,希望对大家有帮助。

本篇文章给大家带来了关于JavaScript的相关知识,其中主要介绍了关于面向对象的相关问题,包括了属性描述符、数据描述符、存取描述符等等内容,下面一起来看一下,希望对大家有帮助。

方法:1、利用“点击元素对象.unbind("click");”方法,该方法可以移除被选元素的事件处理程序;2、利用“点击元素对象.off("click");”方法,该方法可以移除通过on()方法添加的事件处理程序。

本篇文章给大家带来了关于JavaScript的相关知识,其中主要介绍了关于BOM操作的相关问题,包括了window对象的常见事件、JavaScript执行机制等等相关内容,下面一起来看一下,希望对大家有帮助。

foreach不是es6的方法。foreach是es3中一个遍历数组的方法,可以调用数组的每个元素,并将元素传给回调函数进行处理,语法“array.forEach(function(当前元素,索引,数组){...})”;该方法不处理空数组。


Hot AI Tools

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Undress AI Tool
Undress images for free

Clothoff.io
AI clothes remover

AI Hentai Generator
Generate AI Hentai for free.

Hot Article

Hot Tools

WebStorm Mac version
Useful JavaScript development tools

SublimeText3 Mac version
God-level code editing software (SublimeText3)

SublimeText3 Chinese version
Chinese version, very easy to use

Safe Exam Browser
Safe Exam Browser is a secure browser environment for taking online exams securely. This software turns any computer into a secure workstation. It controls access to any utility and prevents students from using unauthorized resources.

Dreamweaver Mac version
Visual web development tools
