---
title: AudioBuffer.copyFromChannel()
slug: Web/API/AudioBuffer/copyFromChannel
translation_of: Web/API/AudioBuffer/copyFromChannel
---
<p>{{ APIRef("Web Audio API") }}</p>

<div>
<p><span class="seoSummary">{{ domxref("AudioBuffer") }}接口的copyFromChannel方法将样本从AudioBuffer的指定通道复制到目标数组中</span></p>
</div>

<h2 id="语法">语法</h2>

<pre class="syntaxbox"><em>myArrayBuffer</em>.copyFromChannel(<em>destination</em>,<em>channelNumber</em>,<em>startInChannel</em>);</pre>

<h3 id="参数">参数</h3>

<dl>
 <dt><em>destination</em></dt>
 <dd>将通道数据复制到的{{domxref("Float32Array")}}</dd>
 <dt><em>channelNumber</em></dt>
 <dd>当前AudioBuffer的通道号，用于复制通道数据。键入channelNumber大于或等于{{domxref("AudioBuffer.numberOfChannels")}}，将会抛出<code>INDEX_SIZE_ERR</code> 的错误</dd>
 <dt><em>startInChannel</em> {{optional_inline}}</dt>
 <dd>用于复制数据的可选偏移量。假如<em>startInChannel比</em>{{domxref("AudioBuffer.length")}}大，将会抛出<code>INDEX_SIZE_ERR</code> 的错误</dd>
</dl>

<h2 id="例子">例子</h2>

<pre class="brush: js">var myArrayBuffer = audioCtx.createBuffer(2, frameCount, audioCtx.sampleRate);
var anotherArray = new Float32Array;
myArrayBuffer.copyFromChannel(anotherArray,1,0);
</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('Web Audio API', '#widl-AudioBuffer-copyFromChannel-void-Float32Array-destination-long-channelNumber-unsigned-long-startInChannel', 'copyFromChannel')}}</td>
   <td>{{Spec2('Web Audio API')}}</td>
   <td> </td>
  </tr>
 </tbody>
</table>

<h2 id="浏览器兼容性">浏览器兼容性</h2>

{{Compat("api.AudioBuffer.copyFromChannel")}}

<h2 id="See_also">See also</h2>

<ul>
 <li><a href="/en-US/docs/Web/API/Web_Audio_API/Using_Web_Audio_API">Using the Web Audio API</a></li>
</ul>