代码如下
<video id="video" controls="" style="display:none;width:160px;"  preload="none" mediagroup="myVideoGroup"  poster="http://media.w3.org/2010/05/sintel/poster.png">
        <source id="mp4" src="http://media.w3.org/2010/05/sintel/trailer.mp4" type="video/mp4">
        <p>Your user agent does not support the HTML5 Video element.</p>
    </video>
    <button onclick="play()">play()</button>
    <script>
       function play() {
           var video = document.getElementById("video");
           video.style.cssText +="display:block";
           video.play();
       }
    </script>