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

<div>
<p>{{ domxref("OscillatorNode") }} 的 <code>frequency 属性的接口</code>是 <a href="/en-US/docs/Web/API/AudioParam#a-rate">a-rate</a> {{domxref("AudioParam")}}，表示振荡的频率，单位HZ（hertz）</p>
</div>

<h2 id="语法">语法</h2>

<pre class="brush: js">var oscillator = audioCtx.createOscillator();
oscillator.frequency.value = 440; // value in hertz</pre>

<div class="note">
<p><strong>Note</strong>: 虽然返回的 <code>AudioParam</code> 是只读的，但是它表示的值不是。</p>
</div>

<h3 id="值">值</h3>

<p>一个 <a href="/en-US/docs/Web/API/AudioParam#a-rate">a-rate</a> {{domxref("AudioParam")}} 的值</p>

<h2 id="示例">示例</h2>

<p>下列示例使用 {{ domxref("AudioContext") }} 创建了一个 oscillator node. 这是一个用于展示的示例，查看 <a href="http://mdn.github.io/violent-theremin/">Violent Theremin demo</a> (<a href="https://github.com/mdn/violent-theremin/blob/gh-pages/scripts/app.js">see app.js</a> 是相关代码).</p>

<pre class="brush: js;highlight[8]">// create web audio api context
var audioCtx = new (window.AudioContext || window.webkitAudioContext)();

// create Oscillator node
var oscillator = audioCtx.createOscillator();

oscillator.type = 'square';
oscillator.frequency.value = 440; // value in hertz
oscillator.start();</pre>

<h2 id="说明">说明</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-OscillatorNode-frequency', 'frequency')}}</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.OscillatorNode.frequency")}}

<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>