问题遇到的现象和发生背景
<!DOCTYPE html>
<html>
<body>
<div id="app">
<el-container style="height: 100%; border: 1px solid #eee">
<el-aside width="200px" style="background-color: rgb(238, 241, 246)">
<el-menu :default-openeds="['1','2', '3']">
<el-submenu index="1">
<template slot="title"><i class="el-icon-message"></i>学生管理模块</template>
<el-menu-item-group>
<template slot="title">学生功能</template>
<el-menu-item index="1-1">基本信息</el-menu-item>
<el-menu-item index="1-2">上传文档</el-menu-item>
</el-menu-item-group>
<el-submenu index="1-4">
<template slot="title">项目负责人功能</template>
<el-menu-item index="1-5">创建团队</el-menu-item>
<el-menu-item index="1-6">创建项目</el-menu-item>
</el-submenu>
</el-submenu>
<el-submenu index="2">
<template slot="title"><i class="el-icon-menu"></i>教师功能模块</template>
<el-menu-item-group>
<template slot="title">教师功能</template>
<el-menu-item index="2-1">管理项目</el-menu-item>
<el-menu-item index="2-2">项目里程碑</el-menu-item>
<el-menu-item index="2-3">管理团队</el-menu-item>
<el-menu-item index="2-4">基本信息</el-menu-item>
</el-menu-item-group>
</el-submenu>
<el-submenu index="3">
<template slot="title"><i class="el-icon-setting"></i>管理员功能模块</template>
<el-menu-item-group>
<template slot="title">管理员功能</template>
<el-menu-item index="3-1">修改密码</el-menu-item>
</el-menu-item-group>
</el-submenu>
</el-menu>
</el-aside>
<el-container>
<el-header>
<el-form :inline="true" :model="admin" class="demo-form-inline">
<el-form-item label="学号">
<el-input v-model="admin.ano" placeholder="学号"></el-input>
</el-form-item>
<el-form-item label="班级">
<el-select v-model="admin.classname" placeholder="班级">
<el-option label="1班" value="1班"></el-option>
<el-option label="2班" value="2班"></el-option>
<el-option label="3班" value="3班"></el-option>
<el-option label="4班" value="4班"></el-option>
</el-select>
</el-form-item>
<el-form-item>
<el-button type="primary" @click="onSubmit">查询</el-button>
</el-form-item>
</el-form>
</el-header>
<!--批量删除、添加按钮-->
<el-row>
<el-button type="primary"@click="dialogVisible = true">增加</el-button>
<el-button type="danger">批量删除</el-button>
</el-row>
<!--弹出对话框-->
<el-dialog
title="编辑信息"
:visible.sync="dialogVisible"
width="30%"
>
<el-form ref="admin" :model="admin" label-width="80px">
<el-form-item label="学号">
<el-input v-model="admin.ano"></el-input>
</el-form-item>
<el-form-item label="姓名">
<el-input v-model="admin.name"></el-input>
</el-form-item>
<el-form-item label="性别">
<el-input v-model="admin.gender"></el-input>
</el-form-item>
<el-form-item label="QQ号">
<el-input v-model="admin.qq"></el-input>
</el-form-item>
<el-form-item label="角色">
<el-select v-model="admin.role" placeholder="请选择角色">
<el-option label="负责人" value="1"></el-option>
<el-option label="成员" value="2"></el-option>
</el-select>
</el-form-item>
<el-form-item label="班级">
<el-select v-model="admin.classname" placeholder="请选择班级">
<el-option label="1班" value="1班"></el-option>
<el-option label="2班" value="2班"></el-option>
<el-option label="3班" value="3班"></el-option>
<el-option label="4班" value="4班"></el-option>
</el-select>
</el-form-item>
<el-form-item>
<el-button type="primary" @click="addAdmin">立即添加</el-button>
<el-button @click="dialogVisible = false">取消</el-button>
</el-form-item>
</el-form>
</el-dialog>
<!--数据表格展示-->
<el-main>
<el-table :data="tableData"
:row-class-name="tableRowClassName"
@selection-change="handleSelectionChange">
<el-table-column
type="selection"
width="55">
</el-table-column>
<el-table-column
type="index"
width="50">
</el-table-column>
<el-table-column prop="sno" label="学号" align="center">
</el-table-column>
<el-table-column prop="name" label="姓名" align="center">
</el-table-column>
<el-table-column prop="gender" label="性别" align="center">
</el-table-column>
</el-table-column>
<el-table-column prop="role" label="角色" align="center">
</el-table-column>
</el-table-column>
<el-table-column prop="classname" label="班级" align="center">
</el-table-column>
</el-table-column>
<el-table-column prop="qq" label="QQ号" align="center">
</el-table-column>
</el-table-column>
<el-table-column prop="score" label="分数" align="center">
</el-table-column>
<el-table-column
fixed="right"
label="操作"
width="100">
<template slot-scope="scope">
<el-button @click="handleClick(scope.row)" type="text" size="small">查看</el-button>
<el-button type="text" size="small">编辑</el-button>
</template>
</el-table-column>
</el-table>
</el-main>
</el-container>
</el-container>
</el-container>
</div>
</body>
<!-- import Vue before Element -->
<script src="https://cdn.jsdelivr.net/npm/vue@2.6.14"></script>
<!-- import JavaScript -->
<script src="https://unpkg.com/element-ui/lib/index.js"></script>
<script src="https://unpkg.com/axios/dist/axios.min.js"></script>
<script>
new Vue({
el: '#app',
mounted: function () {
//当页面加载完成后，发送异步请求，获取数据
var _this = this;
axios({
method: "get",
url: "http://localhost:8080/javaweb_war/selectAllServlet"
}).then(function (resp) {
_this.tableData = resp.data;
})
},
</script>
</html>
运行结果及报错内容
DevTools 无法加载来源映射：无法加载 chrome-extension://ncennffkjdiamlpmcbajkmaiiiddgioo/js/xl-content.js.map 的内容：系统错误: net::ERR_BLOCKED_BY_CLIENT
