blocks|key|2777172|text|String#toUpperCase方法不会更新原始字符串，它只返回大写字符串。因此，您需要通过返回的值更新属性值。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|2777173|​|2777174|var+string+=+{
++text:+'This+is+a+string+inside+an+object',
};


console.log(string.text);

string.text+=+string.text.toUpperCase();

console.log(string.text);|code-block|syntax|javascript|2777175|2777176|entityMap|0|LINK|mutability|MUTABLE|url|https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/toUpperCase^0|0|I|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|T|8|@]|9|@$A|U|B|V|1|W]]|C|$]]|$1|D|3|E|5|6|7|X|8|@]|9|@]|C|$]]|$1|F|3|G|5|H|7|Y|8|@]|9|@]|C|$I|J]]|$1|K|3|E|5|6|7|Z|8|@]|9|@]|C|$]]|$1|L|3|-4|5|6|7|10|8|@]|9|@]|C|$]]]|M|$N|$5|O|P|Q|C|$R|S]]]]

<p>The <strong><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/toUpperCase" rel="nofollow"><code>String#toUpperCase</code></a></strong> method  wouldn't update the original string it just returns the capitalized string. So you need to update the property value by the returned value.</p>

<p><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 string = {
  text: 'This is a string inside an object',
};


console.log(string.text);

string.text = string.text.toUpperCase();

console.log(string.text);</code></pre>
</div>
</div>
</p>


blocks|key|1450038|text|.toUpperCase()不更改原始字符串，但返回一个新字符串。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1450039|试一试：|1450040|​|1450041|var+string+=+{
++text:+'This+is+a+string+inside+an+object',
};


console.log(string.text);

string.text+=+string.text.toUpperCase();

console.log(string.text);|code-block|syntax|javascript|1450042|1450043|entityMap^0|0|E|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|R|8|@$9|S|A|T|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|U|8|@]|D|@]|E|$]]|$1|H|3|I|5|6|7|V|8|@]|D|@]|E|$]]|$1|J|3|K|5|L|7|W|8|@]|D|@]|E|$M|N]]|$1|O|3|I|5|6|7|X|8|@]|D|@]|E|$]]|$1|P|3|-4|5|6|7|Y|8|@]|D|@]|E|$]]]|Q|$]]

<p><code>.toUpperCase()</code> does not change the original string, but returns a new string.</p>

<p>Try this instead:</p>

<p><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 string = {
  text: 'This is a string inside an object',
};


console.log(string.text);

string.text = string.text.toUpperCase();

console.log(string.text);</code></pre>
</div>
</div>
</p>


blocks|key|1450056|text|.toUpperCase();返回大写字符串，但不修改原始参数。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1450057|entityMap^0|0|F|0^^$0|@$1|2|3|4|5|6|7|H|8|@$9|I|A|J|B|C]]|D|@]|E|$]]|$1|F|3|-4|5|6|7|K|8|@]|D|@]|E|$]]]|G|$]]

<p><code>.toUpperCase();</code> returns an uppercase string but it does not modify the original argument</p>


blocks|key|1445708|text|从下面的MDN链接:+JavaScript字符串是不可变的。这意味着，一旦创建了一个字符串，就不可能修改它。但是，仍然可以根据对原始字符串的操作创建另一个字符串。例如:toUpperCase()|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1445709|structures|offset|length|1445710|从下面的MDN链接:+toUpperCase()方法返回转换为大写的字符串的值。toUpperCase()不影响字符串本身的值。|1445711|Objects/String/toUpperCase|1445712|entityMap|0|LINK|mutability|MUTABLE|url|https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures|1|https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/toUpperCase^0|0|0|A|0|0|0|0|Q|1|0^^$0|@$1|2|3|4|5|6|7|T|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|U|8|@]|9|@$D|V|E|W|1|X]]|A|$]]|$1|F|3|G|5|6|7|Y|8|@]|9|@]|A|$]]|$1|H|3|I|5|6|7|Z|8|@]|9|@$D|10|E|11|1|12]]|A|$]]|$1|J|3|-4|5|6|7|13|8|@]|9|@]|A|$]]]|K|$L|$5|M|N|O|A|$P|Q]]|R|$5|M|N|O|A|$P|S]]]]

<p>From MDN link below: JavaScript strings are immutable. This means that once a string is created, it is not possible to modify it. However, it is still possible to create another string based on an operation on the original string. For example:toUpperCase()</p>

<p><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures" rel="nofollow">https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures</a></p>

<p>From MDN link below: The toUpperCase() method returns the value of the string converted to upper case. toUpperCase() does not affect the value of the string itself.</p>

<p><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/toUpperCase" rel="nofollow">https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/toUpperCase</a></p>


<p>I'm currently trying to get to grips with passing by reference vs. value, and from what I understand, JS objects are passed by reference.</p>

<p>If that is the case, why does the second console.log statement not produce a capitalised version of the object property?</p>

<p>Any clarification would be great!!!</p>

<p><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 string = {
  text: 'This is a string inside an object',
};


console.log(string.text);

string.text.toUpperCase();

console.log(string.text);</code></pre>
</div>
</div>
</p>


Javascript - I thought this would change

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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我目前正试图处理传递引用与值之间的关系，据我所知，JS对象是通过引用传递的。如果是这样的话，为什么第二个console.log语句不生成对象属性的大写版本？任何澄清都会很好！​var string = {  text: 'This is a string inside an object',};console.log(...

问Javascript -我以为这会改变
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