Vue 高级使用

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 就是对的封装。

  • 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>我的按钮</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.xml");
      
                  //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&currentPage=" + 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.fasterxml.jackson.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.xml");
                  //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 +
                              "&currentPage=" + 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&currentPage=" + 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.xml");
                  //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 +
                          "&currentPage=" + 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&currentPage=" + 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.xml");
                  //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.调用实现类对象修改方法
                  mapper.updateStu(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“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 +
                              "&currentPage=" + 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&currentPage=" + 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.xml");
                  //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);
      
posted @ 2022-01-02 23:08  Alien_Xx  阅读(124)  评论(0编辑  收藏  举报