JavaScript 实现简易钢琴特效：按键监听与音频播放

代码实现与运行效果

<!DOCTYPE html>
<html lang="en">
<head>
 <meta charset="UTF-8">
 <title>Title</title>
 <style>
  *{
   margin: 0;
   padding: 0;
  }
  div{
   height: 50px;
   width: 630px;
   /*background-color: red;*/
   position: absolute;
   top: 300px;
   left: 50%;
   transform: translateX(-50%);
  }
  ul{
   height: 100%;
   width: 100%;
   list-style: none;
   display: flex;
   overflow: hidden;
   border: 1px solid #000;
  }
  li{
   height: 100%;
   width: 100%;
   /*background-color: yellow;*/
   position: relative;
   border-right: 1px dashed #000;
  }
  li:last-child{
   border-right:none
  }
  span{
   width: 70px;
   height: 50px;
   background-color: skyblue;
   position: absolute;
   left: 0;
   top: 50px;
   z-index: -1;
  }
  a{
   text-decoration: none;color: #000;
   line-height: 50px;
   position: absolute;
   left: 50%;
   transform: translateX(-50%);
   font-size: 20px;
   cursor: default;
  }

 </style>
</head>
<body>
<div id="box">
 <ul id="ul">
  <li><a href="">1</a><span></span>
   <audio src="source/a1.mp3"></audio></li>
  <li><a href="">2</a><span></span>
   <audio src="source/a2.mp3"></audio></li>
  <li><a href="">3</a><span></span>
   <audio src="source/a3.mp3"></audio></li>
  <li><a href="">4</a><span></span>
   <audio src="source/a4.mp3"></audio></li>
  <li><a href="">5</a><span></span>
   <audio src="source/a5.mp3"></audio></li>
  <li><a href="">6</a><span></span>
   <audio src="source/a6.mp3"></audio></li>
  <li><a href="">7</a><span></span>
   <audio src="source/a7.mp3"></audio></li>
  <li><a href="">8</a><span></span>
   <audio src="source/a8.mp3"></audio></li>
  <li><a href="">9</a><span></span>
   <audio src="source/a9.mp3"></audio></li>
 </ul>
</div>
<script src="MyTools.js"></script>
<script>
 var allLis = myTool.$('ul').children;
 document.addEventListener('keydown',function (ev) {
  var keyCode = ev['keyCode'] - 49;
  myTool.slowMoving(allLis[keyCode].children[1], {"top": 0}, function () {
   myTool.slowMoving(allLis[keyCode].children[1], {"top": 50});
   // 2.3 播音乐
   allLis[keyCode].children[2].play();
   allLis[keyCode].children[2].currentTime = 0;
  });
 },false);
</script>
</body>
</html>