--- title: AudioContext.createDelay() slug: Web/API/AudioContext/createDelay translation_of: Web/API/BaseAudioContext/createDelay --- <p>{{ APIRef("Web Audio API") }}</p> <div> <p> <code>createDelay() 是 </code> {{ domxref("AudioContext") }} 的一个方法,作用是将输入音频信号延迟一定时间。(比如可以实现 对着话筒说句话,然后几秒后 这句话从音响里播放出来)</p> <p> </p> </div> <h2 id="语法">语法</h2> <pre class="brush: js">var audioCtx = new AudioContext(); var synthDelay = audioCtx.createDelay(<em>maxDelayTime</em>);</pre> <h3 id="参数">参数</h3> <dl> <dt><em>maxDelayTime</em></dt> <dd>设置最大允许延迟的时间,以“秒”为单位</dd> </dl> <h3 id="返回">返回</h3> <p>A {{domxref("DelayNode")}}. The default {{domxref("DelayNode.delayTime")}} if no parameter is passed to <code>createDelay()</code> is 0 seconds.</p> <p>以上是原文,大意是返回延时时间,没有设置时默认是0</p> <p> </p> <h2 id="示例">示例</h2> <p>首先是中文版的简洁的示例,这个例子中 话筒里接收到的声音 会延迟3秒 从音响中播放</p> <pre>window.AudioContext = window.AudioContext || window.webkitAudioContext || window.mozAudioContext || window.msAudioContext; <code>try {//音频相关api var audioContext = new window.AudioContext(); </code> var synthDelay = <code>audioContext</code>.createDelay(5.0); <code>} catch (e) { alert("你浏览器不支持"); } var error = function (error) {alert("有错误"); }; //以下是获取麦克风 if (navigator.getUserMedia) { //标准api navigator.getUserMedia({ "audio": true }, function (stream) { micto(stream); //具体工作 }, error); }else if(navigator.webkitGetUserMedia) { //webkit api navigator.webkitGetUserMedia({audio:true, video: false }, function (stream) { micto(stream); //具体工作 }, error); }else if (navigator.mozGetUserMedia) { //火狐 api navigator.mozGetUserMedia({ "audio": true }, function (stream) { micto(stream);//具体工作 }, error); }else if (navigator.msGetUserMedia) { //ie api navigator.msGetUserMedia({ "audio": true }, function (stream) { micto(stream);//具体工作 }, error); } else { alert("您的浏览器版不支持这个api"); } var micto = function(stream) { synthDelay.delayTime.value = 3.0; //延迟3秒 var source = audioContext.createMediaStreamSource(stream); source.connect(synthDelay); synthDelay.connect(audioContext.destination); } </code></pre> <p> </p> <p> 以下是英文版示例</p> <p>We have created a simple example that allows you to play three different samples on a constant loop — see <a href="http://chrisdavidmills.github.io/create-delay/">create-delay</a> (you can also <a href="https://github.com/chrisdavidmills/create-delay">view the source code</a>). If you just press the play buttons, the loops will start immediately; if you slide the sliders up to the right, then press the play buttons, a delay will be introduced, so the looping sounds don't start playing for a short amount of time.</p> <pre class="brush: js;highlight[4,15,16,21,22]">var AudioContext = window.AudioContext || window.webkitAudioContext; var audioCtx = new AudioContext(); var synthDelay = audioCtx.createDelay(5.0); ... var synthSource; playSynth.onclick = function() { synthSource = audioCtx.createBufferSource(); synthSource.buffer = buffers[2]; synthSource.loop = true; synthSource.start(); synthSource.connect(synthDelay); synthDelay.connect(destination); this.setAttribute('disabled', 'disabled'); } stopSynth.onclick = function() { synthSource.disconnect(synthDelay); synthDelay.disconnect(destination); synthSource.stop(); playSynth.removeAttribute('disabled'); } ... var delay1; rangeSynth.oninput = function() { delay1 = rangeSynth.value; synthDelay.delayTime.value = delay1; } </pre> <h2 id="Specifications">Specifications</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-createDelay-DelayNode-double-maxDelayTime', 'createDelay()')}}</td> <td>{{Spec2('Web Audio API')}}</td> <td> </td> </tr> </tbody> </table> <h2 id="Browser_compatibility">Browser compatibility</h2> <div>{{CompatibilityTable}}</div> <div id="compat-desktop"> <table class="compat-table"> <tbody> <tr> <th>Feature</th> <th>Chrome</th> <th>Edge</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>{{CompatVersionUnknown}}</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>Edge</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>{{CompatVersionUnknown}}</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>