function dele(x){
m=document.getElementById("table1");
var n=m.removeChild(m.childNodes[x]);
document.write(n);
}
</script>
</head>
<body>
<table border="1" width="50%" id="table1">
<tr>
<th>学号</th>
<th>姓名</th>
<th>操作</th>
</tr>
<tr>
<td>xh001</td>
<td>王小明</td>
<td><a href="javascript:;" onClick="dele(1)">删除</a></td> <!--在删除按钮上添加点击事件 -->
m=document.getElementById("table1"); 改成
var m=document.getElementById("table1");