JavaScript动态生成HTML表格并实现删除功能

<!DOCTYPE html>
<html lang="zh-CN">
<head>
 <meta charset="UTF-8">
 <meta name="viewport" content="width=device-width, initial-scale=1.0">
 <title>动态生成表格</title>
 <style>
  table {
   border-collapse: collapse;
   margin-top: 200px;
   margin-left: 500px;
  }
  table th{
   border: 1px solid black;
   width: 80px;
   height: 40px;
   text-align: center;
   background-color: cornsilk;
  }

  table td{
   
   border: 1px solid black;
   width: 80px;
   height: 40px;
   text-align: center;

  }

 </style>
</head>
<body>
 <table>
  <thead>
   <tr>
    <th>姓名</th>
    <th>科目</th>
    <th>成绩</th>
    <th>操作</th>
   </tr>
  </thead>
  <tbody>
   <!-- <tr>
    <td>张三</td>
    <td>JavaScript</td>
    <td>100</td>
    <td><a href="JavaScript:;" >删除</a></td>
   </tr>
   <tr>
    <td>李四</td>
    <td>JavaScript</td>
    <td>95</td>
    <td><a href="JavaScript:;" >删除</a></td>
   </tr>
   <tr>
    <td>王五</td>
    <td>JavaScript</td>
    <td>98</td>
    <td><a href="JavaScript:;" >删除</a></td>
   </tr>
   <tr>
    <td>赵六</td>
    <td>JavaScript</td>
    <td>91</td>
    <td><a href="JavaScript:;" >删除</a></td>
   </tr> -->
  </tbody>
 </table>
 <script>

  //加入数据
  var datas = [
   {
    name:'张三',
    subject:'JavaScript',
    score:'100'
   },
   {
    name:'李四',
    subject:'JavaScript',
    score:'95'
   },
   {
    name:'王五',
    subject:'JavaScript',
    score:'98'
   },
   {
    name:'赵六',
    subject:'JavaScript',
    score:'92'
   }
  ];
  //创建行，有几个人就创建几行
  var tbody =document.querySelector('tbody')
  for(var i = 0 ; i < datas.length ; i++){
   //创建行
   var tr = document.createElement('tr');
   tbody.appendChild(tr);
   //创建单元格
   for (var k in datas[i] ){
    var td = document.createElement("td");
    td.innerText = datas[i][k];
    tr.appendChild(td);
   }
   //创建删除单元格
   var td = document.createElement('td');
   td.innerHTML = '<a href="JavaScript:;" >删除</a>';
   tr.appendChild(td);
  }
  var as = document.querySelectorAll('a');
  for (var i = 0 ; i <as.length ; i++){
   as[i].onclick = function(){
    //点击a 删除当前行
    tbody.removeChild(this.parentNode.parentNode);
   }
  }

  // for (var k in Obj){
  //  k 得到的是属性名
  //  dbj[k] 得到的是属性值
  // }
 </script>
</body>
</html>