<!DOCTYPE html>
<html>
<body>
<video id="myVideo" width="320" height="176" controls oncanplaythrough="myFunction()">
<source src="https://www.sample-videos.com/video321/flv/240/big_buck_bunny_240p_10mb.flv" type="video/mp4">
<source src="https://www.sample-videos.com/video321/flv/240/big_buck_bunny_240p_10mb.flv" type="video/ogg">
Your browser does not support HTML5 video.
</video>
<script>
function myFunction() {
alert("Can play the video without buffering");
}
</script>
<p>This example demonstrates how to use the "oncanplaythrough" attribute on a VIDEO element.</p>
<p>Video courtesy of <a href="https://www.bigbuckbunny.org/" target="_blank">Big Buck Bunny</a>.</p>
</body>
</html>