<html> <body> <video controls onprogress="myFunction()"> <source src="mov_bbb.mp4" type="video/mp4"> <source src="mov_bbb.ogg" type="video/ogg"> 您的浏览器不支持 HTML5 video 视频。</video><p>视频由 <a href="https://www.bigbuckbunny.org/" target="_blank">Big Buck Bunny</a> 提供。</p><script>function myFunction() { alert("正在下载视频");}</script></body> </html>