blocks|key|3242840|text|使用localStorage方法设置、获取和删除令牌。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|3242841|查看此链接以获得更多详细信息：https://developer.mozilla.org/en-US/docs/Web/API/Window/localStorage|offset|length|3242842|为了检查令牌是否存在，您可以这样做：|3242843|const+isAuth+=+!!localStorage.token|code-block|syntax|javascript|3242844|entityMap|0|LINK|mutability|MUTABLE|url|https://developer.mozilla.org/en-US/docs/Web/API/Window/localStorage^0|0|F|1W|0|0|0|0^^$0|@$1|2|3|4|5|6|7|U|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|V|8|@]|9|@$D|W|E|X|1|Y]]|A|$]]|$1|F|3|G|5|6|7|Z|8|@]|9|@]|A|$]]|$1|H|3|I|5|J|7|10|8|@]|9|@]|A|$K|L]]|$1|M|3|-4|5|6|7|11|8|@]|9|@]|A|$]]]|N|$O|$5|P|Q|R|A|$S|T]]]]

Use localStorage methods for setting, getting and removing token.
Check this link for more details: <a href="https://developer.mozilla.org/en-US/docs/Web/API/Window/localStorage" rel="nofollow noreferrer">https://developer.mozilla.org/en-US/docs/Web/API/Window/localStorage</a>
And for checking weather the token exists or not you can do this:
<pre><code>const isAuth = !!localStorage.token
</code></pre>

blocks|key|3242868|text|可以使用removeItem()从本地存储中删除项。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|3242869|localStorage.removeItem('token')|code-block|syntax|javascript|3242870|您还可以使用函数getItem()检索该项。|3242871|localStorage.getItem('token')|3242872|这将在不存在时返回null。|3242873|3242874|文档|blockquote|3242875|3242876|https://developer.mozilla.org/en-US/docs/Web/API/Storage/getItem|offset|length|3242877|https://developer.mozilla.org/en-US/docs/Web/API/Storage/setItem|3242878|https://blog.logrocket.com/localstorage-javascript-complete-guide/|3242879|entityMap|0|LINK|mutability|MUTABLE|url|1|2^0|0|0|0|0|0|0|0|0|0|1S|0|0|0|1S|1|0|0|1U|2|0^^$0|@$1|2|3|4|5|6|7|18|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|19|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|1A|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|1B|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|1C|8|@]|9|@]|A|$]]|$1|M|3|-4|5|6|7|1D|8|@]|9|@]|A|$]]|$1|N|3|O|5|P|7|1E|8|@]|9|@]|A|$]]|$1|Q|3|-4|5|6|7|1F|8|@]|9|@]|A|$]]|$1|R|3|S|5|6|7|1G|8|@]|9|@$T|1H|U|1I|1|1J]]|A|$]]|$1|V|3|W|5|6|7|1K|8|@]|9|@$T|1L|U|1M|1|1N]]|A|$]]|$1|X|3|Y|5|6|7|1O|8|@]|9|@$T|1P|U|1Q|1|1R]]|A|$]]|$1|Z|3|-4|5|6|7|1S|8|@]|9|@]|A|$]]]|10|$11|$5|12|13|14|A|$15|S]]|16|$5|12|13|14|A|$15|W]]|17|$5|12|13|14|A|$15|Y]]]]

You can use removeItem() to remove items from your localstorage.
<pre><code>localStorage.removeItem('token')
</code></pre>
You can also use the function getItem() to retrieve the item.
<pre><code>localStorage.getItem('token')
</code></pre>
This will return null when it doesn't exist.
<blockquote>
Documentation
<a href="https://developer.mozilla.org/en-US/docs/Web/API/Storage/getItem" rel="nofollow noreferrer">https://developer.mozilla.org/en-US/docs/Web/API/Storage/getItem</a>
<a href="https://developer.mozilla.org/en-US/docs/Web/API/Storage/setItem" rel="nofollow noreferrer">https://developer.mozilla.org/en-US/docs/Web/API/Storage/setItem</a>
<a href="https://blog.logrocket.com/localstorage-javascript-complete-guide/" rel="nofollow noreferrer">https://blog.logrocket.com/localstorage-javascript-complete-guide/</a>
</blockquote>

blocks|key|2710876|text|本地存储只能保存字符串。这是一个简单的生活事实。这就是为什么JSON.parse和JSON.stringify是读写本地存储的同义词。null也不例外。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|2710877|entityMap^0|U|A|15|E|0^^$0|@$1|2|3|4|5|6|7|H|8|@$9|I|A|J|B|C]|$9|K|A|L|B|C]]|D|@]|E|$]]|$1|F|3|-4|5|6|7|M|8|@]|D|@]|E|$]]]|G|$]]

Local storage can only save strings. That is a simple fact of life.
This is why <code>JSON.parse</code> and <code>JSON.stringify</code> are synonymous with reading and writing from and to local storage.
null is no exception.

blocks|key|2710916|text|给出一个值或用函数集项覆盖本地存储中的值，如下所示：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|2710917|localStorage.setItem('token'+,+'your+token+here+');|code-block|syntax|javascript|2710918|为获取该值：|2710919|localStorage.getItem('token')
window.console.log("token+:",localStorage.getItem('token'))|2710920|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|N|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

give a value or overwrite the one present in the localstorage with the function set item, like code below :
<pre><code>localStorage.setItem('token' , 'your token here ');
</code></pre>
and for access the value :
<pre><code>localStorage.getItem('token')
window.console.log(&quot;token :&quot;,localStorage.getItem('token'))
</code></pre>

blocks|key|2710941|text|浏览器中的本地存储仅适用于字符串类型。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|2710942|localStorage.getItem('someItem');
localStorage.setItem('someItem',+'string+value');
localStorage.removeItem('someItem');|code-block|syntax|javascript|2710943|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

Localstorage in the browsers work only on the string types
<pre><code>localStorage.getItem('someItem');
localStorage.setItem('someItem', 'string value');
localStorage.removeItem('someItem');
</code></pre>

I am coming from Java dev and new to javascript, can someone explains what is going on.
I am using <code>localStorage</code> to store my token in my browser.
<pre class="lang-js prettyprint-override"><code>localStorage.token = 'xxx'
</code></pre>
When the users sign out, we remove the token, here is the code
<pre class="lang-js prettyprint-override"><code>localStorage.token = null
</code></pre>
If we want to check wether the user is authenticated or not, we check the token
<pre class="lang-js prettyprint-override"><code>const isAuth = localStorage.token !== null
</code></pre>
Here is the thing becomes weird to me. After I marked <code>localStorage.token</code> to <code>null</code>,
the result of <code>localStorage.token !== null</code> is still true !
 
I had done some investigation,
I logged the <code>localStorage</code> object and found out the <code>token</code> variable is <code>&quot;null&quot;</code> instead of <code>null</code>.
Here is my assumption.
When the browser needs to store the localStorage, it iterates inside the object fields, after finding the <code>null</code> object, it use <code>toString</code> to store the final form?

Null object is String type in localStorage

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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我来自Java，刚开始使用javascript，有人能解释一下发生了什么吗？我使用localStorage将令牌存储在浏览器中。localStorage.token = 'xxx'当用户签出时，我们删除令牌，这是代码localStorage.token = null如果我们想检查用户是否经过身份验证，我们将检查令牌。c...

问空对象是localStorage中的字符串类型。
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问空对象是localStorage中的字符串类型。EN