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---
title: Object.getOwnPropertySymbols()
slug: Web/JavaScript/Reference/Global_Objects/Object/getOwnPropertySymbols
tags:
- ECMAScript 2015
- JavaScript
- Method
- Object
translation_of: Web/JavaScript/Reference/Global_Objects/Object/getOwnPropertySymbols
---
<div>{{JSRef}}</div>
<p><code><strong>Object.getOwnPropertySymbols()</strong></code> 方法返回一个给定对象自身的所有 Symbol 属性的数组。</p>
<h2 id="Syntax" name="Syntax">语法</h2>
<pre class="syntaxbox"><code>Object.getOwnPropertySymbols(<em>obj</em>)</code></pre>
<h3 id="Parameters" name="Parameters">参数</h3>
<dl>
<dt><code>obj</code></dt>
<dd>要返回 Symbol 属性的对象。</dd>
<dt>
<h3 id="返回值">返回值</h3>
</dt>
<dd>在给定对象自身上找到的所有 Symbol 属性的数组。</dd>
</dl>
<h2 id="Description" name="Description">描述</h2>
<p>与{{jsxref("Object.getOwnPropertyNames()")}}类似，您可以将给定对象的所有符号属性作为 Symbol 数组获取。 请注意，{{jsxref("Object.getOwnPropertyNames()")}}本身不包含对象的 Symbol 属性，只包含字符串属性。</p>
<p>因为所有的对象在初始化的时候不会包含任何的 Symbol，除非你在对象上赋值了 Symbol 否则<code>Object.getOwnPropertySymbols()</code>只会返回一个空的数组。</p>
<h2 id="示例">示例</h2>
<pre class="brush: js">var obj = {};
var a = Symbol("a");
var b = Symbol.for("b");
obj[a] = "localSymbol";
obj[b] = "globalSymbol";
var objectSymbols = Object.getOwnPropertySymbols(obj);
console.log(objectSymbols.length); // 2
console.log(objectSymbols) // [Symbol(a), Symbol(b)]
console.log(objectSymbols[0]) // Symbol(a)
</pre>
<h2 id="规范">规范</h2>
<table class="standard-table">
<tbody>
<tr>
<th scope="col">Specification</th>
<th scope="col">Status</th>
<th scope="col">Comment</th>
</tr>
<tr>
<td>{{SpecName('ES2015', '#sec-object.getownpropertysymbols', 'Object.getOwnPropertySymbols')}}</td>
<td>{{Spec2('ES2015')}}</td>
<td>Initial definition.</td>
</tr>
<tr>
<td>{{SpecName('ESDraft', '#sec-object.getownpropertysymbols', 'Object.getOwnPropertySymbols')}}</td>
<td>{{Spec2('ESDraft')}}</td>
<td> </td>
</tr>
</tbody>
</table>
<h2 id="浏览器兼容">浏览器兼容</h2>
<div class="hidden">The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out <a href="https://github.com/mdn/browser-compat-data">https://github.com/mdn/browser-compat-data</a> and send us a pull request.</div>
<p>{{Compat("javascript.builtins.Object.getOwnPropertySymbols")}}</p>
<h2 id="相关链接">相关链接</h2>
<ul>
<li>{{jsxref("Object.getOwnPropertyNames()")}}</li>
<li>{{jsxref("Symbol")}}</li>
</ul>
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