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---
title: AudioBuffer.length
slug: Web/API/AudioBuffer/length
translation_of: Web/API/AudioBuffer/length
---
<p>{{ APIRef("Web Audio API") }}</p>
<div>
<p>The <code>length</code> property of the {{ domxref("AudioBuffer") }} interface returns an integer representing the length, in sample-frames, of the PCM data stored in the buffer.</p>
<p>{{ domxref("AudioBuffer") }} 的length属性接口返回整数，该整数代表采样帧中，存贮在缓冲区中的PCM数据的长度</p>
</div>
<h2 id="语法">语法</h2>
<pre class="brush: js;highlight[22]">var myArrayBuffer = audioCtx.createBuffer(2, frameCount, audioCtx.sampleRate);
myArrayBuffer.length;</pre>
<h3 id="值">值</h3>
<p>浮点数</p>
<h2 id="例子">例子</h2>
<pre class="brush: js;highlight[22]">// 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;
}
}
console.log(myArrayBuffer.length);
}</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-length', 'length')}}</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.length")}}
<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>
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