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---
title: AudioContext.createBufferSource()
slug: Web/API/AudioContext/createBufferSource
tags:
- API
- 音源
- 音频源
- 音频节点
translation_of: Web/API/BaseAudioContext/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 < channels; channel++) {
// This gives us the actual ArrayBuffer that contains the data
var nowBuffering = myArrayBuffer.getChannelData(channel);
for (var i = 0; i < 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>
<div>{{CompatibilityTable}}</div>
<div id="compat-desktop">
<table class="compat-table">
<tbody>
<tr>
<th>Feature</th>
<th>Chrome</th>
<th>Firefox (Gecko)</th>
<th>Internet Explorer</th>
<th>Opera</th>
<th>Safari (WebKit)</th>
</tr>
<tr>
<td>Basic support</td>
<td>{{CompatChrome(10.0)}}{{property_prefix("webkit")}}</td>
<td>{{CompatGeckoDesktop(25.0)}} </td>
<td>{{CompatNo}}</td>
<td>15.0{{property_prefix("webkit")}}<br>
22 (unprefixed)</td>
<td>6.0{{property_prefix("webkit")}}</td>
</tr>
</tbody>
</table>
</div>
<div id="compat-mobile">
<table class="compat-table">
<tbody>
<tr>
<th>Feature</th>
<th>Android</th>
<th>Firefox Mobile (Gecko)</th>
<th>Firefox OS</th>
<th>IE Mobile</th>
<th>Opera Mobile</th>
<th>Safari Mobile</th>
<th>Chrome for Android</th>
</tr>
<tr>
<td>Basic support</td>
<td>{{CompatUnknown}}</td>
<td>26.0</td>
<td>1.2</td>
<td>{{CompatUnknown}}</td>
<td>{{CompatUnknown}}</td>
<td>{{CompatUnknown}}</td>
<td>33.0</td>
</tr>
</tbody>
</table>
</div>
<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>
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