课堂讲义
1、Vue 高级使用
1.1、自定义组件
学完了 Element 组件后，我们会发现组件其实就是自定义的标签。例如<el-button>就是对<button>的封装
本质上，组件是带有一个名字且可复用的 Vue 实例，我们完全可以自己定义
定义格式
Vue.component(组件名称, {
props:组件的属性,
data: 组件的数据函数,
template: 组件解析的标签模板
})代码实现
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>自定义组件</title>
<script src="vue/vue.js"></script>
</head>
<body>
<div id="div">
<my-button></my-button>
</div>
</body>
<script>
Vue.component("my-button",{
// 属性
props:["style"],
// 数据函数
data: function(){
return{
msg:"我的按钮"
}
},
//解析标签模板
template:"<button style='color:red'>{{msg}}</button>"
});
new Vue({
el:"#div"
});
</script>
</html>
1.2、Vue的生命周期
生命周期
生命周期的八个阶段
代码实现
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>生命周期</title>
<script src="vue/vue.js"></script>
</head>
<body>
<div id="app">
{{message}}
</div>
</body>
<script>
let vm = new Vue({
el: '#app',
data: {
message: 'Vue的生命周期'
},
beforeCreate: function() {
console.group('------beforeCreate创建前状态------');
console.log("%c%s", "color:red", "el : " + this.$el); //undefined
console.log("%c%s", "color:red", "data : " + this.$data); //undefined
console.log("%c%s", "color:red", "message: " + this.message);//undefined
},
created: function() {
console.group('------created创建完毕状态------');
console.log("%c%s", "color:red", "el : " + this.$el); //undefined
console.log("%c%s", "color:red", "data : " + this.$data); //已被初始化
console.log("%c%s", "color:red", "message: " + this.message); //已被初始化
},
beforeMount: function() {
console.group('------beforeMount挂载前状态------');
console.log("%c%s", "color:red", "el : " + (this.$el)); //已被初始化
console.log(this.$el);
console.log("%c%s", "color:red", "data : " + this.$data); //已被初始化
console.log("%c%s", "color:red", "message: " + this.message); //已被初始化
},
mounted: function() {
console.group('------mounted 挂载结束状态------');
console.log("%c%s", "color:red", "el : " + this.$el); //已被初始化
console.log(this.$el);
console.log("%c%s", "color:red", "data : " + this.$data); //已被初始化
console.log("%c%s", "color:red", "message: " + this.message); //已被初始化
},
beforeUpdate: function() {
console.group('beforeUpdate 更新前状态===============》');
let dom = document.getElementById("app").innerHTML;
console.log(dom);
console.log("%c%s", "color:red", "el : " + this.$el);
console.log(this.$el);
console.log("%c%s", "color:red", "data : " + this.$data);
console.log("%c%s", "color:red", "message: " + this.message);
},
updated: function() {
console.group('updated 更新完成状态===============》');
let dom = document.getElementById("app").innerHTML;
console.log(dom);
console.log("%c%s", "color:red", "el : " + this.$el);
console.log(this.$el);
console.log("%c%s", "color:red", "data : " + this.$data);
console.log("%c%s", "color:red", "message: " + this.message);
},
beforeDestroy: function() {
console.group('beforeDestroy 销毁前状态===============》');
console.log("%c%s", "color:red", "el : " + this.$el);
console.log(this.$el);
console.log("%c%s", "color:red", "data : " + this.$data);
console.log("%c%s", "color:red", "message: " + this.message);
},
destroyed: function() {
console.group('destroyed 销毁完成状态===============》');
console.log("%c%s", "color:red", "el : " + this.$el);
console.log(this.$el);
console.log("%c%s", "color:red", "data : " + this.$data);
console.log("%c%s", "color:red", "message: " + this.message);
}
});
// 销毁Vue对象
//vm.$destroy();
//vm.message = "hehe"; // 销毁后 Vue 实例会解绑所有内容
// 设置data中message数据值
vm.message = "good...";
</script>
</html>
1.3、Vue异步操作***
在Vue中发送异步请求，本质上还是AJAX。我们可以使用axios这个插件来简化操作！
使用步骤 1.引入axios核心js文件。 2.调用axios对象的方法来发起异步请求。 3.调用axios对象的方法来处理响应的数据。
axios常用方法
代码实现
html代码
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>异步操作</title>
<script src="js/vue.js"></script>
<script src="js/axios-0.18.0.js"></script>
</head>
<body>
<div id="div">
{{name}}
<button @click="send()">发起请求</button>
</div>
</body>
<script>
new Vue({
el:"#div",
data:{
name:"张三"
},
methods:{
send(){
// GET方式请求
// axios.get("testServlet?name=" + this.name)
// .then(resp => {
// alert(resp.data);
// })
// .catch(error => {
// alert(error);
// })
// POST方式请求
axios.post("testServlet","name="+this.name)
.then(resp => {
alert(resp.data);
})
.catch(error => {
alert(error);
})
}
}
});
</script>
</html>java代码
package com.itheima;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
@WebServlet("/testServlet")
public class TestServlet extends HttpServlet {
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
//设置请求和响应的编码
req.setCharacterEncoding("UTF-8");
resp.setContentType("text/html;charset=UTF-8");
//获取请求参数
String name = req.getParameter("name");
System.out.println(name);
//响应客户端
resp.getWriter().write("请求成功");
}
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
this.doGet(req,resp);
}
}
1.4、小结
自定义组件：本质上，组件是带有一个名字且可复用的 Vue 实例，我们可以自己来定义。
Vue.component(组件名称, {
props:组件的属性,
data: 组件的数据函数,
template: 组件解析的标签模板
})生命周期：核心八个阶段 beforeCreate：创建前 created：创建后 beforeMount：载入前 mounted：载入后 beforeUpdate：更新前 updated：更新后 beforeDestroy：销毁前 destroyed：销毁后
异步操作：通过 axios 插件来实现。
2、综合案例 学生管理系统***
2.1、效果环境的介绍
2.2、登录功能的实现
环境搭建
从当天的资料中解压《学生管理系统原始项目》，并导入。
代码实现
html代码
onSubmit(formName) {
// 为表单绑定验证功能
this.$refs[formName].validate((valid) => {
if (valid) {
//请求服务器完成登录功能
axios.post("userServlet","username=" + this.form.username + "&password=" + this.form.password)
.then(resp => {
if(resp.data == true) {
//登录成功，跳转到首页
location.href = "index.html";
}else {
//登录失败，跳转到登录页面
alert("登录失败，请检查用户名和密码");
location.href = "login.html";
}
})
} else {
return false;
}
});
}java代码
UserServlet.java
package com.itheima.controller;
import com.itheima.bean.User;
import com.itheima.service.UserService;
import com.itheima.service.impl.UserServiceImpl;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.util.List;
@WebServlet("/userServlet")
public class UserServlet extends HttpServlet {
private UserService service = new UserServiceImpl();
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
//设置请求和响应编码
req.setCharacterEncoding("UTF-8");
resp.setContentType("text/html;charset=UTF-8");
//1.获取请求参数
String username = req.getParameter("username");
String password = req.getParameter("password");
//2.封装User对象
User user = new User(username,password);
//3.调用业务层的登录方法
List<User> list = service.login(user);
//4.判断是否查询出结果
if(list.size() != 0) {
//将用户名存入会话域当中
req.getSession().setAttribute("username",username);
//响应给客户端true
resp.getWriter().write("true");
}else {
//响应给客户端false
resp.getWriter().write("false");
}
}
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
doGet(req,resp);
}
}UserService.java
package com.itheima.service;
import com.itheima.bean.User;
import java.util.List;
/*
业务层约束接口
*/
public interface UserService {
/*
登录方法
*/
public abstract List<User> login(User user);
}UserServiceImpl.java
package com.itheima.service.impl;
import com.itheima.bean.User;
import com.itheima.mapper.UserMapper;
import com.itheima.service.UserService;
import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;
import java.io.IOException;
import java.io.InputStream;
import java.util.List;
public class UserServiceImpl implements UserService {
@Override
public List<User> login(User user) {
InputStream is = null;
SqlSession sqlSession = null;
List<User> list = null;
try{
//1.加载核心配置文件
is = Resources.getResourceAsStream("MyBatisConfig.
//2.获取SqlSession工厂对象
SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(is);
//3.通过SqlSession工厂对象获取SqlSession对象
sqlSession = sqlSessionFactory.openSession(true);
//4.获取UserMapper接口的实现类对象
UserMapper mapper = sqlSession.getMapper(UserMapper.class);
//5.调用实现类对象的登录方法
list = mapper.login(user);
}catch (Exception e) {
e.printStackTrace();
} finally {
//6.释放资源
if(sqlSession != null) {
sqlSession.close();
}
if(is != null) {
try {
is.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
//7.返回结果到控制层
return list;
}
}UserMapper.java
package com.itheima.mapper;
import com.itheima.bean.User;
import org.apache.ibatis.annotations.Select;
import java.util.List;
public interface UserMapper {
/*
登录方法
*/
@Select("SELECT * FROM user WHERE username=#{username} AND password=#{password}")
public abstract List<User> login(User user);
}
2.3、分页查询功能的实现
代码实现
html代码
<script>
new Vue({
el:"#div",
data:{
dialogTableVisible4add: false, //添加窗口显示状态
dialogTableVisible4edit: false, //编辑窗口显示状态
formData:{},//添加表单的数据
editFormData: {},//编辑表单的数据
tableData:[],//表格数据
pagination: {
currentPage: 1, //当前页
pageSize: 5, //每页显示条数
total: 0 //总条数
},
rules: {
number: [
{required: true, message: '请输入学号', trigger: 'blur'},
{min: 2, max: 10, message: '长度在 2 到 10 个字符', trigger: 'blur'}
],
name: [
{required: true, message: '请输入姓名', trigger: 'blur'},
{min: 2, max: 10, message: '长度在 2 到 10 个字符', trigger: 'blur'}
],
birthday: [
{required: true, message: '请选择日期', trigger: 'change'}
],
address: [
{required: true, message: '请输入地址', trigger: 'blur'},
{min: 2, max: 200, message: '长度在 2 到 200 个字符', trigger: 'blur'}
],
}
},
methods:{
//分页查询功能
selectByPage(){
axios.post("studentServlet","method=selectByPage¤tPage=" + this.pagination.currentPage + "&pageSize=" + this.pagination.pageSize)
.then(resp => {
//将查询出的数据赋值tableData
this.tableData = resp.data.list;
//设置分页参数
//当前页
this.pagination.currentPage = resp.data.pageNum;
//总条数
this.pagination.total = resp.data.total;
})
},
//改变每页条数时执行的函数
handleSizeChange(pageSize) {
//修改分页查询的参数
this.pagination.pageSize = pageSize;
//重新执行查询
this.selectByPage();
},
//改变页码时执行的函数
handleCurrentChange(pageNum) {
//修改分页查询的参数
this.pagination.currentPage = pageNum;
//重新执行查询
this.selectByPage();
},
showAddStu() {
//弹出窗口
this.dialogTableVisible4add = true;
},
resetForm(addForm) {
//双向绑定，输入的数据都赋值给了formData， 清空formData数据
this.formData = {};
//清除表单的校验数据
this.$refs[addForm].resetFields();
},
showEditStu(row) {
//1. 弹出窗口
this.dialogTableVisible4edit = true;
//2. 显示表单数据
this.editFormData = {
number:row.number,
name:row.name,
birthday:row.birthday,
address:row.address,
}
}
},
mounted(){
//调用分页查询功能
this.selectByPage();
}
});
</script>java代码
1、创建StudentServlet.java
package com.itheima.controller;
import com.fasterjackson.databind.ObjectMapper;
import com.github.pagehelper.Page;
import com.github.pagehelper.PageInfo;
import com.itheima.bean.Student;
import com.itheima.service.StudentService;
import com.itheima.service.impl.StudentServiceImpl;
import org.apache.commons.beanutils.BeanUtils;
import org.apache.commons.beanutils.ConvertUtils;
import org.apache.commons.beanutils.Converter;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Map;
@WebServlet("/studentServlet")
public class StudentServlet extends HttpServlet {
private StudentService service = new StudentServiceImpl();
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
//设置请求和响应编码
req.setCharacterEncoding("UTF-8");
resp.setContentType("text/html;charset=UTF-8");
//1.获取方法名
String method = req.getParameter("method");
if(method.equals("selectByPage")) {
//分页查询功能
selectByPage(req,resp);
}
}
/*
分页查询功能
*/
private void selectByPage(HttpServletRequest req, HttpServletResponse resp) {
//获取请求参数
String currentPage = req.getParameter("currentPage");
String pageSize = req.getParameter("pageSize");
//调用业务层的查询方法
Page page = service.selectByPage(Integer.parseInt(currentPage), Integer.parseInt(pageSize));
//封装PageInfo
PageInfo info = new PageInfo(page);
//将info转成json，响应给客户端
try {
String json = new ObjectMapper().writeValueAsString(info);
resp.getWriter().write(json);
} catch (Exception e) {
e.printStackTrace();
}
}
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
doGet(req,resp);
}
}2、创建StudentService.java
package com.itheima.service;
import com.github.pagehelper.Page;
import com.itheima.bean.Student;
/*
学生业务层接口
*/
public interface StudentService {
/*
分页查询方法
*/
public abstract Page selectByPage(Integer currentPage, Integer pageSize);
}3、创建StudentServiceImpl.java
package com.itheima.service.impl;
import com.github.pagehelper.Page;
import com.github.pagehelper.PageHelper;
import com.itheima.bean.Student;
import com.itheima.mapper.StudentMapper;
import com.itheima.service.StudentService;
import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;
import java.io.IOException;
import java.io.InputStream;
/*
学生业务层实现类
*/
public class StudentServiceImpl implements StudentService {
/*
分页查询功能
*/
@Override
public Page selectByPage(Integer currentPage, Integer pageSize) {
InputStream is = null;
SqlSession sqlSession = null;
Page page = null;
try{
//1.加载核心配置文件
is = Resources.getResourceAsStream("MyBatisConfig. //2.获取SqlSession工厂对象
SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(is);
//3.通过SqlSession工厂对象获取SqlSession对象
sqlSession = sqlSessionFactory.openSession(true);
//4.获取StudentMapper接口实现类对象
StudentMapper mapper = sqlSession.getMapper(StudentMapper.class);
//5.设置分页参数
page = PageHelper.startPage(currentPage,pageSize);
//6.调用实现类对象查询全部方法
mapper.selectAll();
} catch (Exception e) {
e.printStackTrace();
} finally {
//7.释放资源
if(sqlSession != null) {
sqlSession.close();
}
if(is != null) {
try {
is.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
//8.返回结果到控制层
return page;
}
}4、创建StudentMapper.java
package com.itheima.mapper;
import com.itheima.bean.Student;
import org.apache.ibatis.annotations.Delete;
import org.apache.ibatis.annotations.Insert;
import org.apache.ibatis.annotations.Select;
import org.apache.ibatis.annotations.Update;
import java.util.List;
/*
学生持久层接口
*/
public interface StudentMapper {
/*
查询全部方法
*/
@Select("SELECT * FROM student")
public abstract List<Student> selectAll();
}
2.4、添加功能的实现
代码实现
html代码
在stuList.html中增加"添加功能"代码
//添加学生功能 addStu(){ let param = "method=addStu&number=" + this.formData.number + "&name=" + this.formData.name + "&birthday=" + this.formData.birthday + "&address=" + this.formData.address + "¤tPage=" + this.pagination.currentPage + "&pageSize=" + this.pagination.pageSize; axios.post("studentServlet",param) .then(resp => { //将查询出的数据赋值tableData this.tableData = resp.data.list; //设置分页参数 //当前页 this.pagination.currentPage = resp.data.pageNum; //总条数 this.pagination.total = resp.data.total; }) //关闭添加窗口 this.dialogTableVisible4add = false; }java代码
1、在StudentServlet.java中增加"添加功能"代码-addStu
/* *1、直接复制会报错 *2、需要将此行代码需要添加到"doGet"方法中 *3、增加"addStu"方法名的判断 */ else if(method.equals("addStu")) { //添加数据功能 addStu(req,resp); } ================================================================================== /* 添加数据功能 */ private void addStu(HttpServletRequest req, HttpServletResponse resp) { //获取请求参数 Map<String, String[]> map = req.getParameterMap(); String currentPage = req.getParameter("currentPage"); String pageSize = req.getParameter("pageSize"); //封装Student对象 Student stu = new Student(); //注册日期转换器方法 dateConvert(); try { BeanUtils.populate(stu,map); } catch (Exception e) { e.printStackTrace(); } //调用业务层的添加方法 service.addStu(stu); //重定向到分页查询功能 try { resp.sendRedirect(req.getContextPath() + "/studentServlet?method=selectByPage¤tPage=" + currentPage + "&pageSize=" + pageSize); } catch (IOException e) { e.printStackTrace(); } } /* 日期转换 */ private void dateConvert() { ConvertUtils.register(new Converter() { public Object convert(Class type, Object value) { SimpleDateFormat simpleDateFormat = new SimpleDateFormat("yyyy-MM-dd"); try { return simpleDateFormat.parse(value.toString()); } catch (ParseException e) { e.printStackTrace(); } return null; } }, Date.class); }2、在StudentService.java中增加"添加功能"-addStu
/* 添加数据方法 */ public abstract void addStu(Student stu);
3、StudentServiceImpl.java中增加"添加功能"-addStu
/*
添加数据方法
*/
@Override
public void addStu(Student stu) {
InputStream is = null;
SqlSession sqlSession = null;
try{
//1.加载核心配置文件
is = Resources.getResourceAsStream("MyBatisConfig. //2.获取SqlSession工厂对象
SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(is);
//3.通过SqlSession工厂对象获取SqlSession对象
sqlSession = sqlSessionFactory.openSession(true);
//4.获取StudentMapper接口实现类对象
StudentMapper mapper = sqlSession.getMapper(StudentMapper.class);
//5.调用实现类对象添加方法
mapper.addStu(stu);
} catch (Exception e) {
e.printStackTrace();
} finally {
//6.释放资源
if(sqlSession != null) {
sqlSession.close();
}
if(is != null) {
try {
is.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}4、StudentMapper.java中增加"添加功能"-addStu
/*
添加数据方法
*/
@Insert("INSERT INTO student VALUES (#{number},#{name},#{birthday},#{address})")
public abstract void addStu(Student stu);
2.5、修改功能的实现
代码实现
html代码
在stuList.html中增加"修改功能"代码
//修改数据功能
updateStu() {
let param = "method=updateStu&number=" + this.editFormData.number + "&name=" + this.editFormData.name +
"&birthday=" + this.editFormData.birthday + "&address=" + this.editFormData.address +
"¤tPage=" + this.pagination.currentPage + "&pageSize=" + this.pagination.pageSize;
axios.post("studentServlet",param)
.then(resp => {
//将查询出的数据赋值tableData
this.tableData = resp.data.list;
//设置分页参数
//当前页
this.pagination.currentPage = resp.data.pageNum;
//总条数
this.pagination.total = resp.data.total;
})
//关闭编辑窗口
this.dialogTableVisible4edit = false;
}java代码
1、在StudentServlet.java中增加"修改功能"-updateStu
/* 修改数据功能 */ private void updateStu(HttpServletRequest req, HttpServletResponse resp) { //获取请求参数 Map<String, String[]> map = req.getParameterMap(); String currentPage = req.getParameter("currentPage"); String pageSize = req.getParameter("pageSize"); //封装Student对象 Student stu = new Student(); //注册日期转换器方法 dateConvert(); try { BeanUtils.populate(stu,map); } catch (Exception e) { e.printStackTrace(); } //调用业务层的修改方法 service.updateStu(stu); //重定向到分页查询功能 try { resp.sendRedirect(req.getContextPath() + "/studentServlet?method=selectByPage¤tPage=" + currentPage + "&pageSize=" + pageSize); } catch (IOException e) { e.printStackTrace(); } }2、在StudentService.java中增加"修改功能"-updateStu
/* 修改数据方法 */ public abstract void updateStu(Student stu);
3、StudentServiceImpl.java中增加"修改功能"-updateStu
/* *1、直接复制会报错 *2、需要将此行代码需要添加到"doGet"方法中 *3、增加"updateStu"方法名的判断 */ else if(method.equals("updateStu")) { //添加数据功能 updateStu(req,resp); } ==================================================================================/* 修改数据方法 */ @Override public void updateStu(Student stu) { InputStream is = null; SqlSession sqlSession = null; try{ //1.加载核心配置文件 is = Resources.getResourceAsStream("MyBatisConfig.4、StudentMapper.java中增加"修改功能"-updateStu
/* 修改数据方法 */ @Update("UPDATE student SET number=#{number},name=#{name},birthday=#{birthday},address=#{address} WHERE number=#{number}") public abstract void updateStu(Student stu);
2.6、删除功能的实现
代码实现
html代码
在stuList.html中增加"删除功能"代码
//删除数据功能 deleteStu(row) { if(confirm("确定要删除" + row.number + "数据?")) { let param = "method=deleteStu&number=" + row.number + "¤tPage=" + this.pagination.currentPage + "&pageSize=" + this.pagination.pageSize; axios.post("studentServlet",param) .then(resp => { //将查询出的数据赋值tableData this.tableData = resp.data.list; //设置分页参数 //当前页 this.pagination.currentPage = resp.data.pageNum; //总条数 this.pagination.total = resp.data.total; }) } }java代码
1、在StudentServlet.java中增加"删除功能"-
/*
*1、直接复制会报错
*2、需要将此行代码需要添加到"doGet"方法中
*3、增加"deleteStu"方法名的判断
*/
else if(method.equals("deleteStu")) {
//添加数据功能
deleteStu(req,resp);
}
==================================================================================
/*
删除数据功能
*/
private void deleteStu(HttpServletRequest req, HttpServletResponse resp) {
//获取请求参数
String number = req.getParameter("number");
String currentPage = req.getParameter("currentPage");
String pageSize = req.getParameter("pageSize");
//调用业务层的删除方法
service.deleteStu(number);
//重定向到分页查询功能
try {
resp.sendRedirect(req.getContextPath() + "/studentServlet?method=selectByPage¤tPage=" + currentPage + "&pageSize=" + pageSize);
} catch (IOException e) {
e.printStackTrace();
}
}2、在StudentService.java中增加"删除功能"-
/* 删除数据方法 */ public abstract void deleteStu(String number);
3、StudentServiceImpl.java中增加"删除功能"-
/*
删除数据方法
*/
@Override
public void deleteStu(String number) {
InputStream is = null;
SqlSession sqlSession = null;
try{
//1.加载核心配置文件
is = Resources.getResourceAsStream("MyBatisConfig. //2.获取SqlSession工厂对象
SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(is);
//3.通过SqlSession工厂对象获取SqlSession对象
sqlSession = sqlSessionFactory.openSession(true);
//4.获取StudentMapper接口实现类对象
StudentMapper mapper = sqlSession.getMapper(StudentMapper.class);
//5.调用实现类对象删除方法
mapper.deleteStu(number);
} catch (Exception e) {
e.printStackTrace();
} finally {
//6.释放资源
if(sqlSession != null) {
sqlSession.close();
}
if(is != null) {
try {
is.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}4、StudentMapper.java中增加"删除功能"-
/*
删除数据方法
*/
@Delete("DELETE FROM student WHERE number=#{number}")
public abstract void deleteStu(String number);
原文转载：http://www.shaoqun.com/a/586593.html
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