---
title: 赋值运算符(=)
slug: Web/JavaScript/Reference/Operators/Assignment
tags:
  - JavaScript
  - 参考
  - 操作者
  - 语言特性
  - 赋值运算符
translation_of: Web/JavaScript/Reference/Operators/Assignment
---
<div>{{jsSidebar("Operators")}}</div>

<p><span>简单赋值操作符(=)用于为变量赋值。赋值表达式本身的值为其完成后被赋值的变量的值。为了给多个变量赋一个值，可以链式使用赋值操作符。</span></p>

<div>{{EmbedInteractiveExample("pages/js/expressions-assignment.html")}}</div>

<div></div>



<h2 id="语法">语法</h2>

<pre class="syntaxbox notranslate"><strong>Operator:</strong> x = y
</pre>

<h2 id="示例">示例</h2>

<h3 id="简单赋值和链式赋值">简单赋值和链式赋值</h3>

<pre class="brush: js notranslate">// 假设已经存在以下变量
//  x = 5
//  y = 10
//  z = 25

x = y     // x 为 10
x = y = z // x, y 都为 25</pre>

<h2 id="规范">规范</h2>

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  <tr>
   <th scope="col">Specification</th>
  </tr>
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   <td>{{SpecName('ESDraft', '#sec-assignment-operators', 'Assignment operators')}}</td>
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<h2 id="浏览器支持">浏览器支持</h2>



<p>{{Compat("javascript.operators.assignment")}}</p>

<h2 id="相关链接">相关链接</h2>

<ul>
 <li><a href="/en-US/docs/Web/JavaScript/Guide/Expressions_and_Operators#Assignment">Assignment operators in the JS guide</a></li>
</ul>