如何在数组中存储对变量的引用? [英] How can I store reference to a variable within an array?

问题描述

我正在尝试创建一个将字符串映射到变量的数组.似乎该数组存储变量的当前值，而不是存储对该变量的引用.

I'm trying to create an array that maps strings to variables. It seems that the array stores the current value of the variable instead of storing a reference to the variable.

var name = "foo";
var array = [];

array["reference"] = name;

name = "bar";

// Still returns "foo" when I'd like it to return "bar."
array["reference"];

有没有办法使数组引用变量?

Is there a way to make the array refer to the variable?

推荐答案

您不能.

JavaScript 始终 按值传递.一切都是对象； var 存储指针，因此通过指针的值传递.

JavaScript always pass by value. And everything is an object; var stores the pointer, hence it's pass by pointer's value.

如果您的 name ="bar" 应该位于函数内部，则需要传递整个数组.然后，该功能将需要使用 array ["reference"] ="bar" 对其进行更改.

If your name = "bar" is supposed to be inside a function, you'll need to pass in the whole array instead. The function will then need to change it using array["reference"] = "bar".

Btw， [] 是数组文字. {} 是对象文字.该 array ["reference"] 之所以起作用，是因为Array也是一个对象，但是array是要从基于0的索引访问的.您可能想改用 {} .

Btw, [] is an array literal. {} is an object literal. That array["reference"] works because an Array is also an object, but array is meant to be accessed by 0-based index. You probably want to use {} instead.

和 foo ["bar"] 等同于 foo.bar .如果键可以是动态键(例如 foo [bar] )，而不是与foo.bar完全不同(或者如果您要使用最小化器，例如Google的Closure Compiler)，则较长的语法会更有用.

And foo["bar"] is equivalent to foo.bar. The longer syntax is more useful if the key can be dynamic, e.g., foo[bar], not at all the same with foo.bar (or if you want to use a minimizer like Google's Closure Compiler).

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