---
title: Reflect.set()
slug: Web/JavaScript/Reference/Global_Objects/Reflect/set
translation_of: Web/JavaScript/Reference/Global_Objects/Reflect/set
---
<div>{{JSRef}}</div>

<p>静态方法 <code><strong>Reflect</strong></code><strong><code>.set()</code></strong> 工作方式就像在一个对象上设置一个属性。</p>

<h2 id="语法">语法</h2>

<pre class="syntaxbox">Reflect.set(target, propertyKey, value[, receiver])
</pre>

<h3 id="参数">参数</h3>

<dl>
 <dt><code>target</code></dt>
 <dd>设置属性的目标对象。</dd>
 <dt><code>propertyKey</code></dt>
 <dd>设置的属性的名称。</dd>
 <dt><code>value</code></dt>
 <dd>设置的值。</dd>
 <dt><code>receiver</code></dt>
 <dd>如果遇到 <code>setter</code>，<code>receiver</code>则为<code>setter</code>调用时的<code>this</code>值。</dd>
</dl>

<h3 id="返回值">返回值</h3>

<p>返回一个 {{jsxref("Boolean")}} 值表明是否成功设置属性。</p>

<h3 id="异常">异常</h3>

<p>抛出一个 {{jsxref("TypeError")}}，如果目标不是 {{jsxref("Object")}}。</p>

<h2 id="描述">描述</h2>

<p><code>Reflect.set</code> 方法允许你在对象上设置属性。它的作用是给属性赋值并且就像 <a href="/en-US/docs/Web/JavaScript/Reference/Operators/Property_Accessors">property accessor</a> 语法一样，但是它是以函数的方式。 </p>

<h2 id="示例">示例</h2>

<h3 id="使用_Reflect.set">使用 <code>Reflect.set()</code></h3>

<pre class="brush: js">// Object
var obj = {};
Reflect.set(obj, "prop", "value"); // true
obj.prop; // "value"

// Array
var arr = ["duck", "duck", "duck"];
Reflect.set(arr, 2, "goose"); // true
arr[2]; // "goose"

// It can truncate an array.
Reflect.set(arr, "length", 1); // true
arr; // ["duck"];

// With just one argument, propertyKey and value are "undefined".
var obj = {};
Reflect.set(obj); // true
Reflect.getOwnPropertyDescriptor(obj, "undefined");
// { value: undefined, writable: true, enumerable: true, configurable: true }
</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-reflect.set', 'Reflect.set')}}</td>
   <td>{{Spec2('ES6')}}</td>
   <td>Initial definition.</td>
  </tr>
  <tr>
   <td>{{SpecName('ESDraft', '#sec-reflect.set', 'Reflect.set')}}</td>
   <td>{{Spec2('ESDraft')}}</td>
   <td></td>
  </tr>
 </tbody>
</table>

<h2 id="浏览器兼容性">浏览器兼容性</h2>



<p>{{Compat("javascript.builtins.Reflect.set")}}</p>

<h2 id="相关链接">相关链接</h2>

<ul>
 <li>{{jsxref("Reflect")}}</li>
 <li><a href="/en-US/docs/Web/JavaScript/Reference/Operators/Property_Accessors">Property accessors</a></li>
</ul>