files/zh-cn/web/api/baseaudiocontext/createbuffersource/index.html


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---
title: AudioContext.createBufferSource()
slug: Web/API/BaseAudioContext/createBufferSource
tags:
  - API
  - 音源
  - 音频源
  - 音频节点
translation_of: Web/API/BaseAudioContext/createBufferSource
original_slug: Web/API/AudioContext/createBufferSource
---
<p>{{ APIRef("Web Audio API") }}</p>

<div>
<p><code>createBufferSource()</code> 方法用于创建一个新的{{ domxref("AudioBufferSourceNode") }}接口, 该接口可以通过{{ domxref("AudioBuffer") }} 对象来播放音频数据. {{ domxref("AudioBuffer") }}对象可以通过{{domxref("AudioContext.createBuffer")}} 来创建或者通过 {{domxref("AudioContext.decodeAudioData")}}成功解码音轨后获取.</p>
</div>

<h2 id="语法">语法</h2>

<pre class="brush: js">var audioCtx = new AudioContext();
var source = audioCtx.createBufferSource();</pre>

<h2 id="返回">返回</h2>

<p>一个{{domxref("AudioBufferSourceNode")}}对象.</p>

<h2 id="例子">例子</h2>

<p>在这个例子中, 我们将会创建一个2秒的缓冲器,并用白噪音填充它, 然后通过{{ domxref("AudioBufferSourceNode") }}来播放它. </p>

<div class="note">
<p><strong>Note</strong>: You can also <a href="http://mdn.github.io/audio-buffer/">run the code live</a>, or <a href="https://github.com/mdn/audio-buffer">view the source</a>.</p>
</div>

<pre class="brush: js;highlight[31]">var audioCtx = new (window.AudioContext || window.webkitAudioContext)();
var button = document.querySelector('button');
var pre = document.querySelector('pre');
var myScript = document.querySelector('script');

pre.innerHTML = myScript.innerHTML;

// Stereo
var channels = 2;
// Create an empty two second stereo buffer at the
// sample rate of the AudioContext
var frameCount = audioCtx.sampleRate * 2.0;

var myArrayBuffer = audioCtx.createBuffer(2, frameCount, audioCtx.sampleRate);

button.onclick = function() {
  // Fill the buffer with white noise;
  //just random values between -1.0 and 1.0
  for (var channel = 0; channel &lt; channels; channel++) {
   // This gives us the actual ArrayBuffer that contains the data
   var nowBuffering = myArrayBuffer.getChannelData(channel);
   for (var i = 0; i &lt; frameCount; i++) {
     // Math.random() is in [0; 1.0]
     // audio needs to be in [-1.0; 1.0]
     nowBuffering[i] = Math.random() * 2 - 1;
   }
  }

  // Get an AudioBufferSourceNode.
  // This is the AudioNode to use when we want to play an AudioBuffer
  var source = audioCtx.createBufferSource();
  // set the buffer in the AudioBufferSourceNode
  source.buffer = myArrayBuffer;
  // connect the AudioBufferSourceNode to the
  // destination so we can hear the sound
  source.connect(audioCtx.destination);
  // start the source playing
  source.start();
}</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-AudioContext-createBufferSource-AudioBufferSourceNode', 'createBufferSource()')}}</td>
   <td>{{Spec2('Web Audio API')}}</td>
   <td> </td>
  </tr>
 </tbody>
</table>

<h2 id="浏览器支持">浏览器支持</h2>

{{Compat("api.BaseAudioContext.createBufferSource")}}

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

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