兼容IE8的video寫法

 <video width="100%" height="515px" controls preload>
       <source src="1.mp4" type="video/mp4" codecs="avc1.42E01E,mp4a.40.2">
          <!–[if lt IE 8]>
               <embed src="1.mp4" width="100%" height="515px" autostart=false/>
           <![endif]–>
 </video>