<!DOCTYPE html>
<html>
<body>
<p>在此示例中，我们使用 addEventListener() 方法将“ratechange”事件附加到视频元素。 playbackRate 属性用于改变视频的播放速度。</p>
<video id="myVideo" width="320" height="240" autoplay controls>
<source src="movie.mp4" type="video/mp4">
<source src="movie.ogg" type="video/ogg">
您的浏览器不支持 video 视频标签。
</video><br>
<button onclick="setPlaySpeed()" type="button">设置视频慢动作播放</button>
<script>
var x = document.getElementById("myVideo");
function setPlaySpeed() { x.playbackRate = 0.3;
}
x.addEventListener("ratechange", myFunction);
function myFunction() { alert("The playing speed of the video was changed");}
</script>
</body>
</html>