使用javascript创建多维数组

Question

This is a very strange to me actually. 其实这对我来说很奇怪。 I can't figure out how create a multidimensional array dynamically. 我不知道如何动态创建多维数组。 I want to create a three-level drop-down list, so I think I need a three dimensional array to store the values. 我想创建一个三级下拉列表，所以我想我需要一个三维数组来存储值。 How to create three dimensional array? 如何创建三维数组？

<script language=javascript>

var aCourse=new Array();
aCourse[0]=new Array();
aCourse[1]=new Array();
aCourse[2]=new Array();
aCourse[3]=new Array();

aCourse[0][0]="Select...";
aCourse[1][0]="Select...";
aCourse[1][1]="T Square";
aCourse[1][2]="V Square";
aCourse[1][3]="S Square";
aCourse[1][4]="B Square";
aCourse[1][5]="G Square";
aCourse[2][0]="Select...";
aCourse[2][1]="N Square";
aCourse[2][2]="W Square";
aCourse[3][0]="Select…";
aCourse[3][1]="J Square";
aCourse[3][2]="M Square";

function ChangeCourse()
{
var i,
iCategoryIndex;
iCategoryIndex=document.frm.optCategory.selectedIndex;
iCourseCount=0;
while (aCourse[iCategoryIndex][iCourseCount]!=null)
iCourseCount++;
document.frm.optCourse.length=iCourseCount;
for (i=0;i<=iCourseCount-1;i++)
document.frm.optCourse[i]=new Option(aCourse[iCategoryIndex][i]);
document.frm.optCourse.focus();
}

</script>
<body ONfocus=ChangeCourse()>
<h3>Choose category…</h3>
<form name="frm">
<p>Category:
<select name="optCategory" size="1" onChange=ChangeCourse()>
<option>Select…</option>
<option>Soccer</option>
<option>Cricket</option>
<option>Rugby</option>
</select>
</p>
<p>Fields
<select name="optCourse" size="1">
<option>Select…</option>
</select>
</p>
</form>

Answer 1

If your only problem is creating the three-dimensional array, this should work: 如果您唯一的问题是创建三维数组，则此方法应该起作用：

var aCourse = [];

for(var i = 0; i < dimensionOneSize; i++) {
  aCourse[i] = [];
  for(var k = 0; k < dimensionTwoSize; k++)
    aCourse[i][k] = [];
}

It is good to note that JavaScript supports the short-hand definition of an array with square brackets [] , so you can use those to make the dynamic definition cleaner. 值得一提的是，JavaScript支持带有方括号[]的数组的简短定义，因此您可以使用它们来简化动态定义。

Possibly Shorter 可能更短

Also, I'm not sure if this works very well, but it might: 另外，我不确定这是否效果很好，但是可能：

var aCourse = [[[]]];

So far, my testing has not proven a way to use this, but it does validate as a proper script. 到目前为止，我的测试尚未证明使用此功能的方法，但是它确实可以作为适当的脚本进行验证。

Answer 2

First, it's always good to initialize arrays using square brackets, [] : 首先，使用方括号[]初始化数组总是好事：

var aCourse = [];

And to simulate multidimensional arrays in JS, which is essentially an indeterminate number of arrays inside of a single array, do this: 要模拟JS中的多维数组，而JS多维数组本质上是单个数组中不确定数量的数组，请执行以下操作：

aCourse[0] = [];

Or you could create the arrays inside of the square brackets when creating the array: 或者，您可以在创建数组时在方括号内创建数组：

var aCourse = [
    [], [], []
];

This is equivalent to: 这等效于：

aCourse[0] = [];
aCourse[1] = [];
aCourse[2] = [];

使用javascript创建多维数组

问题描述

2 个解决方案

解决方案1
1 已采纳 2012-07-02 01:03:55

Possibly Shorter 可能更短

解决方案2
0 2012-07-02 01:00:29

使用javascript创建多维数组

问题描述

2 个解决方案

解决方案1 1 已采纳 2012-07-02 01:03:55

Possibly Shorter 可能更短

解决方案2 0 2012-07-02 01:00:29

解决方案1
1 已采纳 2012-07-02 01:03:55

解决方案2
0 2012-07-02 01:00:29