​x
 
<!DOCTYPE html> 
<html> 
<body> 
​
<button onclick="changeSource()" type="button">改变视频</button>
<br />
<br />
<video id="video1" controls="controls" autoplay="autoplay">
  <source id="mp4_src" src="/example/html5/mov_bbb.mp4" type="video/mp4">
  <source id="ogg_src" src="/example/html5/mov_bbb.ogg" type="video/ogg">
  Your browser does not support HTML5 video.
</video>
​
<script> 
myVid=document.getElementById("video1");
function changeSource()
  { 
  isSupp=myVid.canPlayType("video/mp4");
  if (isSupp=="")
    {
    myVid.src="movie.ogg";
    }
  else
    {
    myVid.src="movie.mp4";
    }
  myVid.load();
  } 
</script> 
​
</body> 
</html>
​