files/zh-cn/web/api/htmlmediaelement/networkstate/index.html


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---
title: HTMLMediaElement.networkState
slug: Web/API/HTMLMediaElement/networkState
tags:
  - API
  - HTML DOM
  - Web
  - 只读
  - 属性
translation_of: Web/API/HTMLMediaElement/networkState
---
<div>{{APIRef("HTML DOM")}}</div>

<p><span class="seoSummary"> <strong><code>HTMLMediaElement.networkState</code></strong> 属性表示在网络上获取媒体的当前状态。</span></p>

<h2 id="Syntax" name="Syntax">语法</h2>

<pre class="syntaxbox">var networkState = audioOrVideo.networkState;</pre>

<h3 id="取值">取值</h3>

<p>一个 <code>unsigned short</code>。可能的值包括：</p>

<table class="standard-table">
 <thead>
  <tr>
   <th scope="col">常量</th>
   <th scope="col"> 值 </th>
   <th scope="col">描述</th>
  </tr>
 </thead>
 <tbody>
  <tr>
   <td><code>NETWORK_EMPTY</code></td>
   <td>0</td>
   <td>还没有数据。并且 <code>readyState</code> 的值是 <code>HAVE_NOTHING</code>。</td>
  </tr>
  <tr>
   <td><code>NETWORK_IDLE</code></td>
   <td>1</td>
   <td>HTMLMediaElement 是有效的并且已经选择了一个资源,，但是还没有使用网络。</td>
  </tr>
  <tr>
   <td><code>NETWORK_LOADING</code></td>
   <td>2</td>
   <td>浏览器正在下载 HTMLMediaElement 数据。</td>
  </tr>
  <tr>
   <td><code>NETWORK_NO_SOURCE</code></td>
   <td>3</td>
   <td>没有找到 HTMLMediaElement src。</td>
  </tr>
 </tbody>
</table>

<h2 id="例子">例子</h2>

<p>这个例子监听audio元素以开始播放，然后检查是否仍然在加载数据。</p>

<pre class="brush: html">&lt;audio id="example" preload="auto"&gt;
 &lt;source src="sound.ogg" type="audio/ogg" /&gt;
&lt;/audio&gt;

</pre>

<pre class="brush: js">var obj = document.getElementById('example');

obj.addEventListener('playing', function() {

  if (obj.networkState === 2) {
    // Still loading...
  }

});
</pre>

<h2 id="规范">规范</h2>

<table class="standard-table">
 <tbody>
  <tr>
   <th scope="col">规范</th>
   <th scope="col">状态</th>
   <th scope="col">注释</th>
  </tr>
  <tr>
   <td>{{SpecName('HTML WHATWG', "the-video-element.html#htmlmediaelement", "HTMLMediaElement.networkState")}}</td>
   <td>{{Spec2('HTML WHATWG')}}</td>
   <td>未对 {{SpecName('HTML5 W3C')}} 更改</td>
  </tr>
  <tr>
   <td>{{SpecName('HTML5 W3C', "embedded-content-0.html#htmlmediaelement", "HTMLMediaElement.networkState")}}</td>
   <td>{{Spec2('HTML5 W3C')}}</td>
   <td>初始定义。</td>
  </tr>
 </tbody>
</table>

<h2 id="浏览器兼容性">浏览器兼容性</h2>

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

<div id="compat-desktop">
<table class="compat-table">
 <tbody>
  <tr>
   <th>Feature</th>
   <th>Chrome</th>
   <th>Edge</th>
   <th>Firefox (Gecko)</th>
   <th>Internet Explorer</th>
   <th>Opera</th>
   <th>Safari</th>
  </tr>
  <tr>
   <td>Basic support</td>
   <td>{{CompatVersionUnknown}}</td>
   <td>{{CompatVersionUnknown}}</td>
   <td>{{CompatGeckoDesktop("1.9.1")}} [1]</td>
   <td>{{CompatIE("9")}}</td>
   <td>{{CompatUnknown}}</td>
   <td>{{CompatUnknown}}</td>
  </tr>
 </tbody>
</table>
</div>

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

<p>[1]  <code>NETWORK_LOADED</code> 已被移除以与Gecko 2.0的HTML规范一致。{{geckoRelease(2)}}. </p>

<h2 id="See_Also" name="See_Also">另见</h2>

<ul>
 <li>定义它的接口, {{domxref("HTMLMediaElement")}}.</li>
</ul>