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docs/javascript/Reference/Global_Objects/Object/__lookupGetter__.html
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@@ -8,24 +8,24 @@
<h2 id="Summary" name="Summary">概述</h2>
<p><code><strong>__lookupGetter__</strong></code> 方法会返回当前对象上指定属性的<strong>属性读取访问器函数（getter）。</strong></p>
<h2 id="Syntax" name="Syntax">语法</h2>
<pre class="syntaxbox"><code><em>obj</em>.__lookupGetter__(<em>sprop</em>)</code></pre>
<pre><code class="language-javascript"><code><em>obj</em>.__lookupGetter__(<em>sprop</em>)</code></code></pre>
<h3 id="Parameters" name="Parameters">参数</h3>
<dl>
<dt><code>sprop</code></dt>
<dd>属性名</dd>
</dl>
<h2 id="Examples" name="Examples">示例</h2>
<pre class="brush: js">var obj = {
<pre><code class="language-javascript">var obj = {
get foo() {
return Math.random() &gt; 0.5 ? "foo" : "bar";
}
};
obj.__lookupGetter__("foo")
// (function (){return Math.random() &gt; 0.5 ? "foo" : "bar"}) </pre>
// (function (){return Math.random() &gt; 0.5 ? "foo" : "bar"}) </code></pre>
<h2 id="Description" name="Description">附注</h2>
<p><code><strong>__lookupGetter__</strong></code> 方法是非标准的，我们应该使用标准中定义的方法来完成同样的事情，那就是 <a href="Reference/Global_Objects/Object/getOwnPropertyDescriptor" title="Object.getOwnPropertyDescriptor() 方法返回指定对象上一个自有属性对应的属性描述符。（自有属性指的是直接赋予该对象的属性，不需要从原型链上进行查找的属性）"><code>Object.getOwnPropertyDescriptor()</code></a> 方法：</p>
<pre class="brush: js">var obj = {
<pre><code class="language-javascript">var obj = {
get foo() {
return Math.random() &gt; 0.5 ? "foo" : "bar";
}
@@ -33,13 +33,13 @@ obj.__lookupGetter__("foo")
Object.getOwnPropertyDescriptor(obj, "foo").get
// (function (){return Math.random() &gt; 0.5 ? "foo" : "bar"})
</pre>
</code></pre>
<p>如果那个访问器属性是继承来的，你还需要使用 <a href="Reference/Global_Objects/Object/getPrototypeOf" title="Object.getPrototypeOf() 方法返回指定对象的原型（内部[[Prototype]]属性的值）。"><code>Object.getPrototypeOf()</code></a>：</p>
<pre class="brush: js">var obj = {};
<pre><code class="language-javascript">var obj = {};
var prototype = Object.getPrototypeOf(obj);
Object.getOwnPropertyDescriptor(prototype, "foo").get
// function __proto__() {[native code]}
</pre>
</code></pre>
<h2 id="Specifications" name="Specifications">规范</h2>
<p>不属于任何规范。</p>
<h2 id="浏览器兼容性">浏览器兼容性</h2>