用jsp写了个表格删除和添加，删除用了触发事件按，但是触发事件没有反应怎么会是。

问题遇到的现象和发生背景
用代码块功能插入代码，请勿粘贴截图

```javascript
<%@ page language="java" contentType="text/html; charset=utf-8"
    pageEncoding="utf-8"%>
html>
<html>
<head>
<meta charset="utf-8">
<title>表格的添加和删除title>
head>
<script>
    window.onload=function(){
        function del(object){
            var table=object.parentNode.parentNode.parentNode;
            var tr=object.parentNode.parentNode;
            table.removeChild(tr);
        }
    }
script>
<body>
<%!
public class Teacher{
    int id;
    String name;
    String brithday;
    String address;
    double salary;
    String operate;
    public Teacher(int id,String name,String brithday,String address,double salary,String operate){
        this.id=id;
        this.name=name;
        this.brithday=brithday;
        this.address=address;
        this.salary=salary;
        this.operate=operate;
    }
    int getId()
    {
        return id;
    }
    String getName()
    {
        return name;
    }
    String getBrithday()
    {
        return brithday;
    }
    String getAddress()
    {
        return address;
    }
    double getSalary()
    {
        return salary;
    }
    String getOperate()
    {
        return operate;
    }
}
%>
<%
Teacher[] teacher=new Teacher[10];
teacher[0]=new Teacher(11201,"文华","1980-6-12","淮南",6600,"英语");
teacher[1]=new Teacher(11202,"余祥","1984-7-23","合肥",7000,"数据结构");
teacher[2]=new Teacher(11203,"于资","1985-2-1","南京",6700,"离散");
teacher[3]=new Teacher(11204,"卜悦","1991-5-16","合肥",6600,"高等数学");
teacher[4]=new Teacher(11205,"王毅","1987-7-16","芜湖",6600,"线性代数");
teacher[5]=new Teacher(11206,"赵鑫","1988-3-26","合肥",6600,"java");
teacher[6]=new Teacher(11207,"丁莹","1990-11-21","蚌埠",6600,"c++");
teacher[7]=new Teacher(11208,"程明","1984-12-17","合肥",6600,"c语言");
teacher[8]=new Teacher(11209,"张强","1986-9-16","阜阳",6600,"毛概");
teacher[9]=new Teacher(11210,"周霞","1991-5-26","合肥",6600,"思修");
%>
<table align="center" border="2" width="70%">
<tr>
<th>教工号th><th>姓名th><th>出生日期th><th>籍贯th><th>薪水th><th>课程th><th>操作th>
tr>
<%
int i;
for(i=0;i
<tr>
<td align="center"><%=teacher[i].getId() %>td>
<td align="center"><%=teacher[i].getName() %>td>
<td align="center"><%=teacher[i].getBrithday() %>td>
<td align="center"><%=teacher[i].getAddress() %>td>
<td align="center"><%=teacher[i].getSalary() %>td>
<td align="center"><%=teacher[i].getOperate() %>td>
<td align="center"><a href="javascript:void(0);" onclick="del(this)">删除a> 
<a href="#">修改a>
td>
<%}%>
table>
body>
html>
运行结果及报错内容

写个了删除的触发事件但是没有反应是怎么回事

如果你要手动触发就把这个函数再拎出来一份，不然你这个只有加载页面触发，然后下边点击的时候没有这个del函数呀

img

window.onload去掉