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---
title: Reflect.get()
slug: Web/JavaScript/Reference/Global_Objects/Reflect/get
translation_of: Web/JavaScript/Reference/Global_Objects/Reflect/get
---
<div>{{JSRef}}</div>
<p><code><strong>Reflect</strong></code><strong><code>.get()</code></strong>方法与从 对象 (<code>target[propertyKey]</code>) 中读取属性类似，但它是通过一个函数执行来操作的。</p>
<h2 id="语法">语法</h2>
<pre class="syntaxbox">Reflect.get(target, propertyKey[, receiver])
</pre>
<h3 id="参数">参数</h3>
<dl>
<dt><code>target</code></dt>
<dd>需要取值的目标对象</dd>
<dt><code>propertyKey</code></dt>
<dd>需要获取的值的键值</dd>
<dt>receiver</dt>
<dd>如果<code>target</code>对象中指定了<code>getter</code>，<code>receiver</code>则为<code>getter</code>调用时的<code>this</code>值。</dd>
</dl>
<h3 id="返回值">返回值</h3>
<p>属性的值。</p>
<h3 id="异常">异常</h3>
<p>如果目标值类型不是 {{jsxref("Object")}}，则抛出一个 {{jsxref("TypeError")}}。</p>
<h2 id="描述">描述</h2>
<p><code>Reflect.get</code>方法允许你从一个对象中取属性值。就如同<a href="/en-US/docs/Web/JavaScript/Reference/Operators/Property_Accessors">属性访问器</a> 语法，但却是通过函数调用来实现。</p>
<h2 id="实例">实例</h2>
<h3 id="使用_Reflect.get"><code><font face="Open Sans, Arial, sans-serif">使用 </font>Reflect.get()</code></h3>
<pre class="brush: js">// Object
var obj = { x: 1, y: 2 };
Reflect.get(obj, "x"); // 1
// Array
Reflect.get(["zero", "one"], 1); // "one"
// Proxy with a get handler
var x = {p: 1};
var obj = new Proxy(x, {
get(t, k, r) { return k + "bar"; }
});
Reflect.get(obj, "foo"); // "foobar"
</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.get', 'Reflect.get')}}</td>
<td>{{Spec2('ES6')}}</td>
<td>Initial definition.</td>
</tr>
<tr>
<td>{{SpecName('ESDraft', '#sec-reflect.get', 'Reflect.get')}}</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.get")}}</p>
<div id="compat-desktop"></div>
<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>
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