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diff --git a/files/zh-cn/web/javascript/reference/global_objects/reflect/get/index.html b/files/zh-cn/web/javascript/reference/global_objects/reflect/get/index.html new file mode 100644 index 0000000000..340178d61f --- /dev/null +++ b/files/zh-cn/web/javascript/reference/global_objects/reflect/get/index.html @@ -0,0 +1,90 @@ +--- +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> |
