W3Schools 试用编辑器 - W3Schools 中文教程

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<h1>HTML DOM Events</h1>
<h2>The onratechange Event</h2>

<p>Use the addEventListener() method to attach a "ratechange" event to a video element.</p>
<p>Use the playbackRate property to change the speed of the video:</p>

<video id="myVideo" width="320" height="240" autoplay controls>
  <source src="movie.mp4" type="video/mp4">
  <source src="movie.ogg" type="video/ogg">
  Your browser does not support the video tag.
</video><br>

<button onclick="setPlaySpeed()" type="button">Set video to be play in slow motion</button>

// Attach a ratechange event to the video element
video.addEventListener("ratechange", myFunction);

// Set the playback speed to 0.3 (slow motion)
function setPlaySpeed() { 
  video.playbackRate = 0.3;
}

// Alert some text when the playing speed of the video is changed
function myFunction() { 
  document.getElementById("demo").innerHTML = "The playing speed of the video was changed.";
}
</script>

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