如何仅使用字符串访问常量变量 [英] How Can I Access A Constant Variable With Only A String

问题描述

我有以下问题：

const value1 = "some value";
var   value2 = "some value";

console.log(window["value1"]); // undefined
console.log(window["value2"]); // some value

我知道const是块作用域的，这就是我无法通过const访问它的原因窗口对象。我的问题是，有什么方法可以仅使用字符串标识符来访问const变量。

I know that const is block scoped and that is the reason I cannot access it through the window object. My question is, is there any way to access a const variable using only a string identifier.

如果我只能访问 value1，如何获取处理实际值1？

If all I have access to is "value1", how do I get a handle on the actual value1? Is it even possible?

推荐答案

看来，像let和const这样的块作用域声明没有添加到全局对象中，这意味着您无法通过window的属性访问它们。

It appears that, block scope declarations, like let and const, are not added to the global object, meaning you can not access them through a property of window.

请参阅Stack Overflow上的以下相关问题：https://stackoverflow.com/a/28776236/10965456

See this related question on Stack Overflow: https://stackoverflow.com/a/28776236/10965456

eval应该可以工作 eval（ values1），以及Function构造函数 new Function（ return value1）（），尽管我不确定为什么会这样必要。如果需要动态访问某些值，请改用数组，对象或映射。

eval should work eval("values1"), as well as the Function constructor new Function("return value1")(), though I'm not sure why this is necessary. If you need to dynamically access certain values, use an array, object, or map instead.

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