Uncaught TypeError: Cannot read property 'cells' of undefined

Posted 2021-03-05 aivnfjgj

<table border="1" width="50%" id="table">
        <tr>
          <th>学号</th>
          <th>姓名</th>
          <th>操作</th>
        </tr>
        <tr>
          <td>xh001</td>
          <td>阮雌</td>
          <td><a href="javascript:;" onclick="delete(this)">删除</a></td>   <!--在删除按钮上添加点击事件  -->
        </tr>
        <tr>
           <td>xh002</td>
           <td>刘赫</td>
           <td><a href="javascript:;" onclick="delete(this)" >删除</a></td>   <!--在删除按钮上添加点击事件  -->
        </tr>
    </table>
<script>
          var tr=document.getElementsByTagName("tr");
          var td=document.getElementsByTagName("td");
         for(var i=0;i<tr.length;i++){
              var n=1;
                n++;
             var k=0;
             
             var cells=tr[i+n].cells;
             
             var length=tr[i+n].cells.length;
             while(k<cells.length){
                 k++;
             }
//            tr[i+n].cells.innerhtml+="xh00";
            console.log(tr[i+n].cells.length)
         }
     }
</script>
报错：没有找到cells元素，这里是个执行顺序写错了，把while循环写在cells上面，问题得到解决。