---
title: MouseEvent.metaKey
slug: Web/API/MouseEvent/metaKey
translation_of: Web/API/MouseEvent/metaKey
---
<p>{{APIRef("DOM Events")}}</p>

<p><strong><code>MouseEvent.metaKey</code></strong> 为只读属性，返回一个 {{jsxref("Boolean", "布尔值")}}，在鼠标事件发生时，用于指示 <kbd>Meta</kbd> 键是按下状态（<code>true</code>），还是释放状态（<code>false</code>）。</p>

<div class="note">
<p><strong>备注：</strong>在 MAC 键盘上，表示 Command 键（<kbd>⌘</kbd>），在 Windows键盘上，表示 Windows 键（<kbd>⊞</kbd>）。</p>
</div>

<h2 id="语法">语法</h2>

<pre class="syntaxbox">var metaKeyPressed = <em>instanceOfMouseEvent</em>.metaKey
</pre>

<h3 id="返回值">返回值</h3>

<p>一个布尔值。</p>

<h2 id="Example" name="Example">示例</h2>

<pre class="brush: js"> function goInput(e) {
 // 检测 metaKey 值
   if (e.metaKey) {
        // 继续处理事件
     superSizeOutput(e);
   } else {
     doOutput(e);
   }
 }
</pre>

<h2 id="规范">规范</h2>

<table class="standard-table">
 <tbody>
  <tr>
   <th scope="col">规范版本</th>
   <th scope="col">规范状态</th>
   <th scope="col">备注</th>
  </tr>
  <tr>
   <td>{{SpecName('DOM3 Events','#widl-MouseEvent-ctrlKey','MouseEvent.ctrlKey')}}</td>
   <td>{{Spec2('DOM3 Events')}}</td>
   <td>No change from {{SpecName('DOM2 Events')}}.</td>
  </tr>
  <tr>
   <td>{{SpecName('DOM2 Events','#Events-MouseEvent','MouseEvent.ctrlKey')}}</td>
   <td>{{Spec2('DOM2 Events')}}</td>
   <td>Initial definition.</td>
  </tr>
 </tbody>
</table>

<h2 id="Browser_compatibility" name="Browser_compatibility">浏览器兼容性</h2>

<p>{{ CompatibilityTable() }}</p>

<div id="compat-desktop">
<table class="compat-table">
 <tbody>
  <tr>
   <th>Feature</th>
   <th>Firefox (Gecko)</th>
   <th>Chrome</th>
   <th>Internet Explorer</th>
   <th>Opera</th>
   <th>Safari</th>
  </tr>
  <tr>
   <td>Basic support</td>
   <td>{{CompatVersionUnknown()}}</td>
   <td>{{CompatVersionUnknown()}}</td>
   <td>{{CompatVersionUnknown()}}</td>
   <td>{{CompatVersionUnknown()}}</td>
   <td>{{CompatVersionUnknown()}}</td>
  </tr>
 </tbody>
</table>
</div>

<div id="compat-mobile">
<table class="compat-table">
 <tbody>
  <tr>
   <th>Feature</th>
   <th>Firefox Mobile (Gecko)</th>
   <th>Android</th>
   <th>IE Mobile</th>
   <th>Opera Mobile</th>
   <th>Safari Mobile</th>
  </tr>
  <tr>
   <td>Basic support</td>
   <td>{{ CompatUnknown() }}</td>
   <td>{{ CompatUnknown() }}</td>
   <td>{{ CompatUnknown() }}</td>
   <td>{{ CompatUnknown() }}</td>
   <td>{{ CompatUnknown() }}</td>
  </tr>
 </tbody>
</table>
</div>

<h2 id="See_also" name="See_also">相关链接</h2>

<ul>
 <li>{{ domxref("MouseEvent") }}</li>
</ul>