---
title: Symbol.prototype.toString()
slug: Web/JavaScript/Reference/Global_Objects/Symbol/toString
translation_of: Web/JavaScript/Reference/Global_Objects/Symbol/toString
---
<div>{{JSRef("Global_Objects", "Symbol")}}</div>

<h2 id="Summary" name="Summary">概述</h2>

<p><code><strong>toString()</strong></code> 方法返回当前 symbol 对象的字符串表示。</p>

<h2 id="Syntax" name="Syntax">语法</h2>

<pre class="syntaxbox"><var>symbol.toString()</var>;</pre>

<h2 id="Description" name="Description">描述</h2>

<p>{{jsxref("Symbol")}} 对象拥有自己的 <code>toString</code> 方法，因而遮蔽了原型链上的 {{jsxref("Object.prototype.toString()")}}。</p>

<h3 id="symbol_原始值不能转换为字符串">symbol 原始值不能转换为字符串</h3>

<p>symbol 原始值不能转换为字符串，所以只能先转换成它的包装对象，再调用 <code>toString()</code> 方法：</p>

<pre class="brush: js">Symbol("foo") + "bar";
// TypeError: Can't convert symbol to string
Symbol("foo").toString() + "bar"
// "Symbol(foo)bar"，就相当于下面的:
Object(Symbol("foo")).toString() + "bar"
// "Symbol(foo)bar"
</pre>

<h2 id="示例">示例</h2>

<pre class="brush: js">Symbol("desc").toString();   // "Symbol(desc)"

// well-known symbols
Symbol.iterator.toString();  // "Symbol(Symbol.iterator)

// global symbols
Symbol.for("foo").toString() // "Symbol(foo)"
</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('ES6', '#sec-symbol.prototype.tostring', 'Symbol.prototype.toString')}}</td>
   <td>{{Spec2('ES6')}}</td>
   <td>Initial definition.</td>
  </tr>
 </tbody>
</table>

<h2 id="浏览器兼容性">浏览器兼容性</h2>

<p>{{ CompatibilityTable() }}</p>

<div id="compat-desktop">
<table class="compat-table">
 <tbody>
  <tr>
   <th>Feature</th>
   <th>Chrome</th>
   <th>Firefox (Gecko)</th>
   <th>Internet Explorer</th>
   <th>Opera</th>
   <th>Safari</th>
  </tr>
  <tr>
   <td>Basic support</td>
   <td>{{ CompatVersionUnknown() }}</td>
   <td>{{ CompatGeckoDesktop("33.0") }}</td>
   <td>{{ CompatNo() }}</td>
   <td>{{ CompatNo() }}</td>
   <td>{{ CompatNo() }}</td>
  </tr>
 </tbody>
</table>
</div>

<div id="compat-mobile">
<table class="compat-table">
 <tbody>
  <tr>
   <th>Feature</th>
   <th>Android</th>
   <th>Chrome for Android</th>
   <th>Firefox Mobile (Gecko)</th>
   <th>IE Mobile</th>
   <th>Opera Mobile</th>
   <th>Safari Mobile</th>
  </tr>
  <tr>
   <td>Basic support</td>
   <td>{{ CompatVersionUnknown() }}</td>
   <td>{{ CompatVersionUnknown() }}</td>
   <td>{{ CompatGeckoMobile("33.0") }}</td>
   <td>{{ CompatNo() }}</td>
   <td>{{ CompatNo() }}</td>
   <td>{{ CompatNo() }}</td>
  </tr>
 </tbody>
</table>
</div>

<h2 id="See_Also" name="See_Also">相关链接</h2>

<ul>
 <li>{{jsxref("Object.prototype.toString()")}}</li>
</ul>