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语法高亮，滚动条美化，设置页面调整

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docs/javascript/Reference/Errors/Non_configurable_array_element.html
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<article id="wikiArticle">
<div></div>
<h2 id="错误提示">错误提示</h2>
<pre class="syntaxbox">TypeError: can't delete non-configurable array element (Firefox)
<pre><code class="language-javascript">TypeError: can't delete non-configurable array element (Firefox)
TypeError: Cannot delete property '2' of [object Array] (Chrome)
</pre>
</code></pre>
<h2 id="错误类型">错误类型</h2>
<p><a href="Reference/Global_Objects/TypeError" title="TypeError（类型错误） 对象用来表示值的类型非预期类型时发生的错误。"><code>TypeError</code></a></p>
<h2 id="哪里出错了？">哪里出错了？</h2>
@@ -13,37 +13,37 @@ TypeError: Cannot delete property '2' of [object Array] (Chrome)
<h2 id="示例">示例</h2>
<h3 id="通过_Object.defineProperty_创建的不可配置属性"><code><font face="x-locale-heading-primary, zillaslab, Palatino, Palatino Linotype, x-locale-heading-secondary, serif">通过 </font>Object.defineProperty 创建的不可配置属性</code></h3>
<p>使用 <a href="Reference/Global_Objects/Object/defineProperty" title="Object.defineProperty() 方法会直接在一个对象上定义一个新属性，或者修改一个对象的现有属性， 并返回这个对象。"><code>Object.defineProperty()</code></a> 且在没有明确将属性设定为可配置的情况下，默认可以创建不可配置属性。</p>
<pre class="brush: js example-bad">var arr = [];
<pre><code class="language-js example-bad">var arr = [];
Object.defineProperty(arr, 0, {value: 0});
Object.defineProperty(arr, 1, {value: "1"});
arr.length = 1;
// TypeError: can't delete non-configurable array element
</pre>
</code></pre>
<p>如果想要缩短数组长度的话，需要将其中的元素设置为可配置的。</p>
<pre class="brush: js example-good">var arr = [];
<pre><code class="language-js example-good">var arr = [];
Object.defineProperty(arr, 0, {value: 0, configurable: true});
Object.defineProperty(arr, 1, {value: "1", configurable: true});
arr.length = 1;
</pre>
</code></pre>
<h3 id="密封的数组"><code>密封的数组</code></h3>
<p> <a href="Reference/Global_Objects/Object/seal" title="The source for this interactive example is stored in a GitHub repository. If you'd like to contribute to the interactive examples project, please clone https://github.com/mdn/interactive-examples and send us a pull request."><code>Object.seal()</code></a> 函数会将数组中现存的所有元素标记为不可配置。</p>
<pre class="brush: js example-bad">var arr = [1,2,3];
<pre><code class="language-js example-bad">var arr = [1,2,3];
Object.seal(arr);
arr.length = 1;
// TypeError: can't delete non-configurable array element
</pre>
</code></pre>
<p>（为了解决上述问题，）或者是移除 <a href="Reference/Global_Objects/Object/seal" title="The source for this interactive example is stored in a GitHub repository. If you'd like to contribute to the interactive examples project, please clone https://github.com/mdn/interactive-examples and send us a pull request."><code>Object.seal()</code></a> 调用，或者将数组拷贝一份。在拷贝数组的情况下，缩短备份数组的长度并不会修改原始数组的长度。</p>
<pre class="brush: js example-good">var arr = [1,2,3];
<pre><code class="language-js example-good">var arr = [1,2,3];
Object.seal(arr);
// Copy the initial array to shorten the copy
var copy = Array.from(arr);
copy.length = 1;
// arr.length == 3
</pre>
</code></pre>
<h2 id="相关内容">相关内容</h2>
<ul>
<li><a href="/en-US/docs/Web/JavaScript/Data_structures#Properties">[[Configurable]]</a></li>