是否可以在LocalStorage中使用ES6符号 [英] Is it possible to use ES6 Symbols in LocalStorage

问题描述

在将ES6 Symbol用作LocalStorage中键/值对的键时，在重新加载页面后我们还能访问它吗?

When using a ES6 Symbol as the key for a key/value pair in LocalStorage, can we then still access it after reloading the page?

我发现了本教程声称使用Symbol.for时这是可能的，但是到目前为止，当我尝试检索LocalStorage键/值对时，我仍然没有成功并获得undefined.

I found this tutorial that claims this to be possible when using Symbol.for, but so far I have no success and get an undefined when I try to retrieve the LocalStorage key/value pair.

作为附带的问题:在这里使用Symbols是否有意义?

As a side question: does it make sense to use Symbols over here?

推荐答案

您可以将Symbols用作对象中的键-这最终是它们的目的.但是localStorage不是您的典型对象.它具有一个API，用于设置/获取商店中的值，您共享的教程未使用该API:localStorage.{set,get}Item().

You can use Symbols as keys in an object - that's ultimately their purpose. But localStorage is not your typical object. It has an API to set/get values in the store, which the tutorial you have shared is not using: localStorage.{set,get}Item().

不幸的是，localStorage不接受将Symbols作为键，而仅将字符串作为键.因此，真正的答案是否定的，您不能在本地存储中使用符号作为键，但是...

Unfortunately localStorage doesn't accept Symbols as keys, only strings. So the real answer is no, you can't use Symbols as keys in LocalStorage, but...

您可以执行以下操作.它实际上不是使用Symbol作为键，而是Symbols toString()表示形式:

You could do the following. It isn't actually using a Symbol as the key, but the Symbols toString() representation:

const sym = Symbol.for('Hello').toString()
localStorage.setItem(sym, 'World')
document.write('Hello, ' + localStorage.getItem(sym))

[在jsbin.com上查看]

作为附带的问题:在此处使用符号是否有意义?

As a side question: does it make sense to use Symbols over here?

我想您可以使用保留的符号(例如Symbol.iterator)来扩展localStorage全局功能.但这不是重点.

I suppose you could use reserved Symbols (e.g. Symbol.iterator) to extend the functionality of the localStorage global. But that's kind of besides the point.

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