= JavaScript的字符串的构建变量名 [英] Javascript = Building a variable name from strings

问题描述

让我们说我有：

  VAR acDeMa = [10，20，30，40，50];
VAR TEST1 = 5;VAR测试2 = 7;VAR TEST3 = 3;VAR piece1;VAR piece2;VAR piece3;如果（test1的== 5）
{piece1 =AC;}如果（test1的== 7）
{piece2 =德;}如果（test1的== 3）
{piece3 =麻;}
 

我如何再结合这些片段，承认它是从早期的阵列，并从我的数组复制值​​到一个新的阵列？

  VAR finishedArray =（piece1 + piece2 + piece3）;
 

我想下面这个效果，基本上，但无需专门键入它的名字（acDeMa）：

  VAR finishedArray = acDeMa;
 

我将如何去这样做呢？这样做的原因，这是因为我有大约60阵列和我在一个时间比较两个。有些阵列有共同的东西，所以，而不是有独立60'如果'的语句，我会使用如果语句（即巧妙地查找各种阵列的共同点）几个选择在一起，而那条正确的数组名，然后使用我的数组。

没有，我不希望有数字5,7和3的新数组。我想要的数字：10，20，30，40，在finishedArray 50，但由于这些数字可能每次都不同，我不想写的：

  VAR finishedArray = acDeMa;
 

或

  VAR finishedArray = [10，20，30，40，50];
 

解决方案

并不推荐使用，但如果你是在全球范围内的工作，你可以使用这样的窗口对象

  VAR finishedArray =窗口[piece1 + piece2 + piece3];
 

这将创建到原来的数组的引用。为了得到一个单独副本使用片法

  VAR finishedArray =窗口[piece1 + piece2 + piece3] .slice（0）
 

Let's say I have:

var acDeMa = [10, 20, 30, 40, 50];  
var test1 = 5;

var test2 = 7;

var test3 = 3;

var piece1;

var piece2;

var piece3;

if ( test1 == 5 )
{piece1 = "ac";}

if ( test1 == 7 )
{piece2 = "De";}

if ( test1 == 3 )
{piece3 = "Ma";}

How do I then combine those pieces, recognise it as the Array from earlier, and copy the values from my Array into a new Array?

var finishedArray = (piece1 + piece2 + piece3);

I want this effect below, basically, but without having to specifically type it's name (acDeMa):

var finishedArray = acDeMa;

How would I go about doing this? The reason for doing this is because I have about 60 arrays and I'm comparing two at a time. Some of the arrays have things in common, so rather than have 60 separate 'if' statements, I'd rather piece the correct Array name together using a few choice 'if' statements (that cleverly find what various Arrays have in common), and then using that as my Array.

No, I do not want to have the numbers 5, 7, and 3 in a new Array. I want the numbers: 10, 20, 30, 40, 50 in finishedArray, but because those numbers could be different every time, I DON'T want to write:

var finishedArray = acDeMa;

or

var finishedArray = [10, 20, 30, 40, 50];

解决方案

Not really recommended but if you are working in the global context you could use the window object like this

var finishedArray = window[piece1+piece2+piece3];

That will create a reference to your original array. To get a separate copy use the slice method

var finishedArray = window[piece1+piece2+piece3].slice(0)

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