JavaScript does not have two-dimensional arrays. There is no concept of a two-dimensional array in JavaScript, but you can set the value of an array element equal to an array, so that you can simulate the structure of a two-dimensional array; if the value of each element in a three-dimensional array is also an array, you can simulate a three-dimensional array. By analogy, multi-dimensional arrays can be defined through array nesting.
The operating environment of this tutorial: windows7 system, javascript version 1.8.5, Dell G3 computer.
JavaScript does not directly support two-dimensional arrays, but you can set the value of the array element equal to the array, so that the structure of the two-dimensional array can be simulated. If the value of each element in a three-dimensional array is also an array, a three-dimensional array can be simulated. By analogy, a multi-dimensional array can be defined through array nesting.
Example 1
The following defines a two-dimensional array.
var a = [ //定义二维数组 [1.1, 1.2], [2.1, 2.2] ];
Example 2
The following example uses nested for statements to store positive numbers from 1 to 100 in the form of a two-dimensional array to design a two-dimensional array.
var a = []; for (var i = 0; i < 10; i ++) { //行循环 var b = []; //辅助数组 for (var j = 0; j < 10; j ++) { //列循环 b[j] = i * 10 + j + 1; //定义数组b的元素值 } a[i] = b; //把数组b赋值给数组a } console.log(a); //返回1~100的二维数列
The sequence format is as follows:
a = [ [1,2,3,4,5,6,7,8,9,10], [11,12,13,14,15,16,17,18,19,20], [21,22,23,24,25,26,27,28,29,30], [31,32,33,34,35,36,37,38,39,40], [41,42,43,44,45,46,47,48,49,50], [51,52,53,54,55,56,57,58,59,60], [61,62,63,64,65,66,67,68,69,70], [71,72,73,74,75,76,77,78,79,80], [81,82,83,84,85,86,87,88,89,90], [91,92,93,94,95,96,97,98,99,100] ];
Example 3
JavaScript does not support two-dimensional arrays, users can imitate the syntax format of two-dimensional arrays to define array. Although the following writing method is not grammatically compliant, JavaScript will not throw an exception.
var a = []; a[0,0] = 1; a[0,1] = 2; a[1,0] = 3; a[1,1] = 4;
If the length attribute is called, the return value is 2, indicating that there are only two elements, and the values of the elements are read separately.
console.log(a.length); //返回2,说明仅有两个元素有效 console.log(a[0]); //返回3 console.log(a[1]); //返回3
JavaScript treats the subscript of a two-dimensional array as a comma expression, and the return value of its operation is the last value. The assignments in the first two lines of code are overwritten by the assignments in the next two lines of code. Therefore, if the subscript value is determined after calculation and then the access operation is performed, the design can be carried out as follows.
var a = [], i = 1; //初始化变量 while(i < 10) { //指定循环次数 a[i *= 2, i] = i; //指定下标为2的幂数时才进行赋值 } console.log(a.length); //返回17 console.log(a); //返回数组[,,2,,4,,,,8,,,,,,,,16]
【Related recommendations: javascript learning tutorial】
The above is the detailed content of Does JavaScript have two-dimensional arrays?. 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

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.

SublimeText3 Linux new version
SublimeText3 Linux latest version

SublimeText3 Chinese version
Chinese version, very easy to use

Notepad++7.3.1
Easy-to-use and free code editor

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