​x
 
<!DOCTYPE html> 
<html> 
<body> 
​
<button onclick="getVolume()" type="button">音量是多少？</button>
<button onclick="setHalfVolume()" type="button">把音量设置为 0.2</button>
<button onclick="setFullVolume()" type="button">把音量设置为 1.0</button>
<br />
<br />
<video id="video1" controls="controls">
  <source src="/example/html5/mov_bbb.mp4" type="video/mp4">
  <source src="/example/html5/mov_bbb.ogg" type="video/ogg">
  Your browser does not support HTML5 video.
</video>
​
<script>
myVid=document.getElementById("video1");
function getVolume()
  { 
  alert(myVid.volume);
  } 
function setHalfVolume()
  { 
  myVid.volume=0.2;
  } 
function setFullVolume()
  { 
  myVid.volume=1.0;
  } 
</script> 
​
</body> 
</html>
​