blocks|key|2452636|text|目前，所有的实现Safari、WebKit、Chrome、Firefox和IE都遵循WebStorage标准的old+version，其中存储项的值只能是一个字符串。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|2452637|一种选择是使用JSON+parse和stringify方法来序列化和反序列化数据，就像我不久前在another+question中建议的那样，例如：|style|CODE|2452638|​|2452639|var+value+=+"true";
console.log(JSON.parse(value)+===+true);+//+true|code-block|syntax|javascript|2452640|2452641|entityMap|0|LINK|mutability|MUTABLE|url|https://developer.apple.com/library/archive/documentation/iPhone/Conceptual/SafariJSDatabaseGuide/Name-ValueStorage/Name-ValueStorage.html#//apple_ref/doc/uid/TP40007256-CH6-SW1|1|https://developer.mozilla.org/en-US/docs/Web/API/Web_Storage_API|2|https://developer.mozilla.org/en-US/docs/Web/API/Storage/setItem|3|https://www.w3.org/TR/2009/WD-webstorage-20090423/|4|https://stackoverflow.com/questions/2010892/storing-objects-in-html5-localstorage/^0|8|6|0|T|7|1|11|2|2|1J|B|3|0|C|5|I|9|1C|G|4|0|0|0|0^^$0|@$1|2|3|4|5|6|7|15|8|@]|9|@$A|16|B|17|1|18]|$A|19|B|1A|1|1B]|$A|1C|B|1D|1|1E]|$A|1F|B|1G|1|1H]]|C|$]]|$1|D|3|E|5|6|7|1I|8|@$A|1J|B|1K|F|G]|$A|1L|B|1M|F|G]]|9|@$A|1N|B|1O|1|1P]]|C|$]]|$1|H|3|I|5|6|7|1Q|8|@]|9|@]|C|$]]|$1|J|3|K|5|L|7|1R|8|@]|9|@]|C|$M|N]]|$1|O|3|I|5|6|7|1S|8|@]|9|@]|C|$]]|$1|P|3|-4|5|6|7|1T|8|@]|9|@]|C|$]]]|Q|$R|$5|S|T|U|C|$V|W]]|X|$5|S|T|U|C|$V|Y]]|Z|$5|S|T|U|C|$V|10]]|11|$5|S|T|U|C|$V|12]]|13|$5|S|T|U|C|$V|14]]]]

For the moment, all the implementations <a href="https://developer.apple.com/library/archive/documentation/iPhone/Conceptual/SafariJSDatabaseGuide/Name-ValueStorage/Name-ValueStorage.html#//apple_ref/doc/uid/TP40007256-CH6-SW1" rel="noreferrer">Safari</a>, WebKit, Chrome, <a href="https://developer.mozilla.org/en-US/docs/Web/API/Web_Storage_API" rel="noreferrer">Firefox</a> and <a href="https://developer.mozilla.org/en-US/docs/Web/API/Storage/setItem" rel="noreferrer">IE</a>, are following an <a href="https://www.w3.org/TR/2009/WD-webstorage-20090423/" rel="noreferrer">old version</a> of the WebStorage standard, where the value of the storage items can be only a string.
An option would be to use JSON <code>parse</code> and <code>stringify</code> method to serialize and deserialize the data, as I suggested some time ago in <a href="https://stackoverflow.com/questions/2010892/storing-objects-in-html5-localstorage/">another question</a>, for example:
<div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
<div class="snippet-code">
<pre class="snippet-code-js lang-js prettyprint-override"><code>var value = "true";
console.log(JSON.parse(value) === true); // true</code></pre>
</div>
</div>

blocks|key|1488088|text|我的解决方案：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1488089|function+tytPreGetBool(pre)+{
++++return+localStorage.getItem(pre)+===+'true';
}|code-block|syntax|javascript|1488090|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|$]]

My solutions:

<pre><code>function tytPreGetBool(pre) {
 return localStorage.getItem(pre) === 'true';
}
</code></pre>

blocks|key|745040|text|这与CMS的答案有关。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|745041|下面是我用来处理这个问题的解析部分的一个小函数(该函数将在浏览器实现赶上规范之后继续做正确的事情，所以不需要记住稍后更改代码)：|745042|function+parse(type)+{
+++return+typeof+type+==+'string'+?+JSON.parse(type)+:+type;
}|code-block|syntax|javascript|745043|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|L|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|M|8|@]|9|@]|A|$G|H]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

This is related to CMS’s answer.

Here’s a little function I’ve been using to handle the parsing part of this issue (the function will keep doing the Right Thing after the browser implementations catch up with the spec, so no need to remember to change out code later):

<pre><code>function parse(type) {
 return typeof type == 'string' ? JSON.parse(type) : type;
}
</code></pre>

blocks|key|3860793|text|使用store.js|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|3860794|localStorage.setItem('isUser',+true)
localStorage.getItem('isUser')+===+"true"+//true
npm+i+-D+store|code-block|syntax|javascript|3860795|↓|3860796|store.get('isUser')++//true|3860797|entityMap|0|LINK|mutability|MUTABLE|url|https://github.com/marcuswestin/store.js/#user-content-api^0|2|8|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|U|8|@]|9|@$A|V|B|W|1|X]]|C|$]]|$1|D|3|E|5|F|7|Y|8|@]|9|@]|C|$G|H]]|$1|I|3|J|5|6|7|Z|8|@]|9|@]|C|$]]|$1|K|3|L|5|F|7|10|8|@]|9|@]|C|$G|H]]|$1|M|3|-4|5|6|7|11|8|@]|9|@]|C|$]]]|N|$O|$5|P|Q|R|C|$S|T]]]]

Use <a href="https://github.com/marcuswestin/store.js/#user-content-api" rel="nofollow noreferrer">store.js</a>:

<pre><code>localStorage.setItem('isUser', true)
localStorage.getItem('isUser') === "true" //true
npm i -D store
</code></pre>

↓

<pre><code>store.get('isUser') //true
</code></pre>

blocks|key|2452813|text|我想指出的是，只需将普通布尔值包装在对象中，然后使用JSON.stringify创建本地存储内容，然后使用JSON.parse检索它，可能会更容易：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|2452814|let+storeMe+=+{
++myBool:+true
}

localStorage.setItem('test',+JSON.stringify(storeMe))
let+result+=+JSON.parse(localStorage.getItem('test'))|code-block|syntax|javascript|2452815|entityMap^0|Q|E|1H|A|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@$9|N|A|O|B|C]|$9|P|A|Q|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|R|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|S|8|@]|D|@]|E|$]]]|L|$]]

I'd like to point out that it might be kinda easier just to wrap plain boolean value inside object and then, using <code>JSON.stringify</code> create local storage content and other way around, <code>JSON.parse</code> to retrive it:
<pre><code>let storeMe = {
 myBool: true
}

localStorage.setItem('test', JSON.stringify(storeMe))
let result = JSON.parse(localStorage.getItem('test'))

</code></pre>

blocks|key|1491079|text|我通常只是将LocalStore中的值保存为布尔值，然后使用解析方法进行检索，以确保对所有浏览器都适用。我下面的方法是为我的业务逻辑定制的。有时，我可能会将smth存储为'no‘，但仍然需要false作为回报|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1491080|function+toBoolean(str)+{
++++if+(typeof+str+===+'undefined'+%7C%7C+str+===+null)+{
++++++++return+false;
++++}+else+if+(typeof+str+===+'string')+{+++++++++++
++++++++switch+(str.toLowerCase())+{
++++++++case+'false':
++++++++case+'no':
++++++++case+'0':
++++++++case+"":
++++++++++++return+false;
++++++++default:
++++++++++++return+true;
++++++++}
++++}+else+if+(typeof+str+===+'number')+{
++++++++return+str+!==+0
++++}
++++else+{return+true;}
}|code-block|syntax|javascript|1491081|entityMap^0|2N|5|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@$9|N|A|O|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|P|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|Q|8|@]|D|@]|E|$]]]|L|$]]

What I usually do is just save the value in LocalStore as a Boolean, and then retrieve with a parsing method, just to be sure for all browsers. My method below is customized for my business logic. Sometimes I might store smth as 'no' and still need <code>false</code> in return 

<pre><code>function toBoolean(str) {
 if (typeof str === 'undefined' || str === null) {
 return false;
 } else if (typeof str === 'string') { 
 switch (str.toLowerCase()) {
 case 'false':
 case 'no':
 case '0':
 case "":
 return false;
 default:
 return true;
 }
 } else if (typeof str === 'number') {
 return str !== 0
 }
 else {return true;}
}
</code></pre>

blocks|key|742775|text|我不确定LocalStorage是否可以保存布尔值，但我可以告诉您，当您使用alert("true"+==+true);时，它的计算结果永远不会为真，因为您是在隐式地将字符串与布尔值进行比较。这就是为什么要使用true而不是"true"来设置布尔值。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|742776|entityMap^0|12|M|2X|4|34|6|0^^$0|@$1|2|3|4|5|6|7|H|8|@$9|I|A|J|B|C]|$9|K|A|L|B|C]|$9|M|A|N|B|C]]|D|@]|E|$]]|$1|F|3|-4|5|6|7|O|8|@]|D|@]|E|$]]]|G|$]]

I'm not sure if LocalStorage can save boolean values but I can tell you that when you do <code>alert("true" == true);</code> it will never evaluate to true because you are implicitly comparing a string to a boolean. That is why to set boolean values you use <code>true</code> instead of <code>"true"</code>.

blocks|key|1491049|text|在某些情况下，eval也可以谨慎地使用。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1491050|console.log(eval("true")+===+true)+//true|code-block|syntax|javascript|1491051|entityMap^0|7|4|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@$9|N|A|O|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|P|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|Q|8|@]|D|@]|E|$]]]|L|$]]

<code>eval</code> can also be used carefully under some cases.

<pre><code>console.log(eval("true") === true) //true
</code></pre>

I noticed that I cannot set boolean values in <code>localStorage</code>?

<pre><code>localStorage.setItem("item1", true);
alert(localStorage.getItem("item1") + " | " + (localStorage.getItem("item1") == true));
</code></pre>

Always alerts <code>true | false</code> when I try to test <code>localStorage.getItem("item1") == "true"</code> it alerts true ... How can I set an item in <code>localStorage</code> to true?

Even if it's a string, I thought only <code>===</code> would check the type? 

So 

<pre><code>alert("true" == true); // should be true? 
</code></pre>

Cannot set boolean values 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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我注意到我不能在localStorage中设置布尔值localStorage.setItem("item1", true);alert(localStorage.getItem("item1") + " | " + (localStorage.getItem("item1") == true));当我尝试测试localStorage.getItem("item1") == "true"时，总是向t

问无法在LocalStorage中设置布尔值？
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