天马学航——智慧教务系统(移动端)开发日志三

日志摘要：更新了学生选课模块、我的课程模块以及退课的功能，优化了后端数据库的缓存

1、学生选课模块

学生选课模块主要实现，学生根据需求进行选课操作，通过后端查询到所有教师的课程，展示在前端，然后根据前端进行选择,选择后发给后端，后端再进行判断，将选课信息返回前端

界面效果

前端源码

struct SelectCourse {
  @State courses:SCourse[] = []

  aboutToAppear(){
    this.getCourse()
  }

  build() {
    Column({ space: 5 }) {
      Text(" ")
      Row({ space: 10 }) {
        Text(" ")
        Image($r('app.media.back'))
          .width(30)
          .height(30)
          .onClick(function () {
            //返回上一页
            router.back() //直接返回
          })
        Text("学生选课")
          .fontSize(30)
          .fontWeight(FontWeight.Bolder)
      }
      .width('100%')

      Text("----------------------------------------------")
      Text(" ")
      List({space:50}){
        ForEach(
          this.courses,
          course=>{
            ListItem(){
              Row({space:30}){
                Text(" ")
                Column({space:20}){
                  Text(course.cname)
                    .fontColor(Color.Green)
                    .fontSize(15)
                    .fontWeight(FontWeight.Bolder)
                    .fontFamily("楷体")
                    Text("课程号："+course.cid)
                      .fontSize(10)
                      .fontColor(Color.Red)
                    Text("任课教师："+course.tname)
                      .fontSize(10)
                      .fontColor(Color.Green)
                }
                .justifyContent(FlexAlign.Start)
                .alignItems(HorizontalAlign.Start)
                Blank()
                Button("选择")
                  .onClick(()=>{
                    console.log("学生点击了："+course.cname)
                    StudentAddCourse.STA(course.cid,course.cname,course.tname)
                      .then(resp=>{
                        console.log("前端收到消息!"+resp)
                        promptAction.showToast({
                          message: resp,
                          duration: 2000,
                          bottom: 50
                        });
                      })
                  })
              }
              .width('95%')
              .height(150)
              //.padding(20)
              .backgroundColor(Color.White)
              .borderRadius(15)
              .shadow({ radius: 6, color: '#1F000000', offsetX: 2, offsetY: 4 })
            }
          }
        )
      }
      .width('100%')
    }
    .width('100%')
  }
  getCourse(){
    GetCourse.GC()
      .then(resp=>{
        console.log("请求成功"+resp)
        if(resp.length === 0){
          promptAction.showToast({
            message: '暂无可选课程',
            duration: 2000,
            bottom: 50
          });
        }
        this.courses = resp;
      })
  }
}

请求源码

请求所有课程部分

class GetCourse {
  baseURL: string = IP.ip

  GC(): Promise<SCourse[]> {
    return new Promise((resolve, reject) => {
      let Http = http.createHttp()
      Http.request(
        `${this.baseURL}/GCourse`,
        {
          method: http.RequestMethod.GET,
          connectTimeout: 10000,
          readTimeout: 10000
        }
      )
        .then(resp=>{
          if(resp.responseCode === 200){
            console.log("请求成功"+resp.result)
            resolve(JSON.parse(resp.result.toString()))
          }
          else {
            console.log("请求发现异常"+resp.responseCode)
          }
        })
        .catch(error=>{
          console.log("请求失败")
        })
    })
  }
}

const gc = new GetCourse()
export default gc as GetCourse

向后端发送选课结果部分

class StudentAddCourse{
  baseURL: string = IP.ip
  STA(cid:string,cname:string,cteacher:string):Promise<string>{
    const data = {
      cid:cid,
      cname:cname,
      cteacher:cteacher
    }
    return new Promise((resolve, reject) => {
      let httpRequest = http.createHttp()
      httpRequest.request(
        `${this.baseURL}/StuSelectcourse`,
        {
          method:http.RequestMethod.GET,
          extraData:data,
          connectTimeout: 10000,
          readTimeout:10000
        },
      )
        .then(resp=>{
          if(resp.responseCode === 200){
            console.log("请求成功："+resp.result)
            resolve(resp.result.toString())
          }
          else {
            console.log("请求失败："+resp.responseCode)
          }
        })
        .catch(error=>{
          console.log("检查链接!")
        })
    })
  }
}

const aa = new StudentAddCourse()
export default aa as StudentAddCourse

后端源码

请求所有课程部分

public class getCourse extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        resp.setContentType("application/json");
        resp.setCharacterEncoding("UTF-8");

        //Mybatis
        SqlSession sql = MybatisUntills.getSqlSession();
        CourseMapper mapper = sql.getMapper(CourseMapper.class);
        List<SelectCourse> allCourse = mapper.getAllCourse();//执行并返回数据
        for (SelectCourse selectCourse : allCourse) {
            System.out.println(selectCourse.getCid()+selectCourse.getCname()+selectCourse.getTname());
        }
        sql.close();

        //打包
        Gson gson = new Gson();
        String JsonData = gson.toJson(allCourse);
        //发送
        resp.getWriter().write(JsonData);
    }

    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        doGet(req, resp);
    }
}

接收学生选课信息部分

public class StuSelectCourse extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        resp.setContentType("application/json");
        resp.setCharacterEncoding("UTF-8");
        ServletContext c = getServletContext();
        HttpSession session = req.getSession();
        String username = (String) session.getAttribute("username");
        if(username == null){
            username = (String) c.getAttribute("username");
        }

        String cid = req.getParameter("cid");
        String cname = req.getParameter("cname");
        String ct = req.getParameter("cteacher");
        System.out.println("课程号"+cid);

        //Mybatis
        SqlSession sql = MybatisUntills.getSqlSession();
        CourseMapper mapper = sql.getMapper(CourseMapper.class);
        Map<String,Object> map1 = new HashMap<String, Object>();
        map1.put("cid",cid);
        map1.put("sid",username);
        String strings = mapper.showStudentCourse(map1);
        if(strings!=null){
            resp.getWriter().write("后端返回信息：该课程已存在！");
            sql.close();
        }
        else {
            Map<String,Object> map = new HashMap<String, Object>();
            map.put("cid",cid);
            map.put("sid",username);
            int i = mapper.addStudentCourse(map);
            sql.commit();
            if(i==1){
                resp.getWriter().write("后端返回信息：选课成功！");
                System.out.println("成！");
            }
            else {
                resp.getWriter().write("后端返回信息：选课失败！");
            }
            sql.close();
        }
    }

    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        doGet(req, resp);
    }
}

2、我的课程(退课模块)

主要显示该用户选择的所有课程，并提供退课的选项，后端查询，前端显示，前端选择，后端判断，将信息返回前端

界面效果

前端源码

struct MyCourse{
  @State courses:StudentMyCourse[] = []

  aboutToAppear(){
    this.MyCourses()
  }

  build() {
    Column({ space: 5 }) {
      Text(" ")
      Row({ space: 10 }) {
        Text(" ")
        Image($r('app.media.back'))
          .width(30)
          .height(30)
          .onClick(function () {
            //返回上一页
            router.back() //直接返回
          })
        Text("我的课程")
          .fontSize(30)
          .fontWeight(FontWeight.Bolder)
      }
      .width('100%')

      Text("----------------------------------------------")
      Text(" ")
      List({space:50}){
        ForEach(
          this.courses,
          course=>{
            ListItem(){
              Row({space:30}){
                Text(" ")
                Column({space:20}){
                  Text(course.cname)
                    .fontColor(Color.Green)
                    .fontSize(15)
                    .fontWeight(FontWeight.Bolder)
                    .fontFamily("楷体")
                  Text("课程号："+course.cid)
                    .fontSize(10)
                    .fontColor(Color.Red)
                  Text("任课教师："+course.tname)
                    .fontSize(10)
                    .fontColor(Color.Green)
                  Text("上课时间："+course.ctime)
                    .fontSize(10)
                    .fontColor(Color.Green)
                }
                .justifyContent(FlexAlign.Start)
                .alignItems(HorizontalAlign.Start)
                Blank()
                Button("退课")
                  .backgroundColor(Color.Red)
                  .onClick(()=>{
                    console.log("学生点击了："+course.cname)
                    DeletCourse.STA(course.cname,course.cid,course.tname,course.ctime)
                      .then(resp=>{
                        console.log("返回成功"+resp)
                        promptAction.showToast({
                          message: resp,
                          duration: 2000,
                          bottom: 50
                        });
                      })
                  })
              }
              .width('95%')
              .height(150)
              //.padding(20)
              .backgroundColor(Color.White)
              .borderRadius(15)
              .shadow({ radius: 6, color: '#1F000000', offsetX: 2, offsetY: 4 })
            }
          }
        )
      }
      .width('100%')
    }
  }
  MyCourses(){
    GetStudentCourse.GC()
      .then(resp=>{
        console.log("返回信息成功"+resp.toString())
        if(resp.length === 0){
          promptAction.showToast({
            message: '您还没有选课哦~',
            duration: 2000,
            bottom: 50
          });
        }
        this.courses = resp
      })
  }
}

请求源码

请求所选课程

class GetStudentCourse {
  baseURL: string = IP.ip

  GC(): Promise<StudentMyCourse[]> {
    return new Promise((resolve, reject) => {
      let Http = http.createHttp()
      Http.request(
        `${this.baseURL}/GetMyCourse`,
        {
          method: http.RequestMethod.GET,
          connectTimeout: 10000,
          readTimeout: 10000
        }
      )
        .then(resp => {
          if (resp.responseCode === 200) {
            console.log("请求成功" + resp.result)
            resolve(JSON.parse(resp.result.toString()))
          }
          else {
            console.log("请求成功，但是出现问题" + resp.responseCode)
          }
        })
        .catch(error => {
          console.log("请求失败" + error)
        })
    })
  }
}

const sc = new GetStudentCourse()
export default sc as GetStudentCourse

向后端发送退课信息

class DeletCourse {

  baseURL: string = IP.ip

  STA(cname: string, cid: string, tname: string,ctime: string): Promise<string> {
    const data = {
      cname: cname,
      cid: cid,
      tname: tname,
      ctime:ctime
    }
    return new Promise((resolve, reject) => {
      let httpRequest = http.createHttp()
      httpRequest.request(
        `${this.baseURL}/DeletMyCourse`,
        {
          method: http.RequestMethod.GET,
          extraData: data,
          connectTimeout: 10000,
          readTimeout: 10000
        },
      )
        .then(resp=>{
          if(resp.responseCode===200){
            console.log("请求成功！"+resp.result)
            resolve(resp.result.toString())
          }
          else {
            console.log("请求发生错误"+resp.responseCode)
          }
        })
        .catch(err=>{
          console.log("请求失败"+err)
        })
    })
  }
}

const sc = new DeletCourse()
export default sc as DeletCourse

后端代码与选课部分相同，这里不再赘述

3、BUG修复

修复了Mybatis二级缓存溢出导致查询变慢的问题

天马学航——智慧教务系统(移动端)开发日志二

日志摘要：更新了学生选课模块、我的课程模块以及退课的功能，优化了后端数据库的缓存

1、学生选课模块

学生选课模块主要实现，学生根据需求进行选课操作，通过后端查询到所有教师的课程，展示在前端，然后根据前端进行选择,选择后发给后端，后端再进行判断，将选课信息返回前端

界面效果

前端源码

struct SelectCourse {
  @State courses:SCourse[] = []

  aboutToAppear(){
    this.getCourse()
  }

  build() {
    Column({ space: 5 }) {
      Text(" ")
      Row({ space: 10 }) {
        Text(" ")
        Image($r('app.media.back'))
          .width(30)
          .height(30)
          .onClick(function () {
            //返回上一页
            router.back() //直接返回
          })
        Text("学生选课")
          .fontSize(30)
          .fontWeight(FontWeight.Bolder)
      }
      .width('100%')

      Text("----------------------------------------------")
      Text(" ")
      List({space:50}){
        ForEach(
          this.courses,
          course=>{
            ListItem(){
              Row({space:30}){
                Text(" ")
                Column({space:20}){
                  Text(course.cname)
                    .fontColor(Color.Green)
                    .fontSize(15)
                    .fontWeight(FontWeight.Bolder)
                    .fontFamily("楷体")
                    Text("课程号："+course.cid)
                      .fontSize(10)
                      .fontColor(Color.Red)
                    Text("任课教师："+course.tname)
                      .fontSize(10)
                      .fontColor(Color.Green)
                }
                .justifyContent(FlexAlign.Start)
                .alignItems(HorizontalAlign.Start)
                Blank()
                Button("选择")
                  .onClick(()=>{
                    console.log("学生点击了："+course.cname)
                    StudentAddCourse.STA(course.cid,course.cname,course.tname)
                      .then(resp=>{
                        console.log("前端收到消息!"+resp)
                        promptAction.showToast({
                          message: resp,
                          duration: 2000,
                          bottom: 50
                        });
                      })
                  })
              }
              .width('95%')
              .height(150)
              //.padding(20)
              .backgroundColor(Color.White)
              .borderRadius(15)
              .shadow({ radius: 6, color: '#1F000000', offsetX: 2, offsetY: 4 })
            }
          }
        )
      }
      .width('100%')
    }
    .width('100%')
  }
  getCourse(){
    GetCourse.GC()
      .then(resp=>{
        console.log("请求成功"+resp)
        if(resp.length === 0){
          promptAction.showToast({
            message: '暂无可选课程',
            duration: 2000,
            bottom: 50
          });
        }
        this.courses = resp;
      })
  }
}

请求源码

请求所有课程部分

class GetCourse {
  baseURL: string = IP.ip

  GC(): Promise<SCourse[]> {
    return new Promise((resolve, reject) => {
      let Http = http.createHttp()
      Http.request(
        `${this.baseURL}/GCourse`,
        {
          method: http.RequestMethod.GET,
          connectTimeout: 10000,
          readTimeout: 10000
        }
      )
        .then(resp=>{
          if(resp.responseCode === 200){
            console.log("请求成功"+resp.result)
            resolve(JSON.parse(resp.result.toString()))
          }
          else {
            console.log("请求发现异常"+resp.responseCode)
          }
        })
        .catch(error=>{
          console.log("请求失败")
        })
    })
  }
}

const gc = new GetCourse()
export default gc as GetCourse

向后端发送选课结果部分

class StudentAddCourse{
  baseURL: string = IP.ip
  STA(cid:string,cname:string,cteacher:string):Promise<string>{
    const data = {
      cid:cid,
      cname:cname,
      cteacher:cteacher
    }
    return new Promise((resolve, reject) => {
      let httpRequest = http.createHttp()
      httpRequest.request(
        `${this.baseURL}/StuSelectcourse`,
        {
          method:http.RequestMethod.GET,
          extraData:data,
          connectTimeout: 10000,
          readTimeout:10000
        },
      )
        .then(resp=>{
          if(resp.responseCode === 200){
            console.log("请求成功："+resp.result)
            resolve(resp.result.toString())
          }
          else {
            console.log("请求失败："+resp.responseCode)
          }
        })
        .catch(error=>{
          console.log("检查链接!")
        })
    })
  }
}

const aa = new StudentAddCourse()
export default aa as StudentAddCourse

后端源码

请求所有课程部分

public class getCourse extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        resp.setContentType("application/json");
        resp.setCharacterEncoding("UTF-8");

        //Mybatis
        SqlSession sql = MybatisUntills.getSqlSession();
        CourseMapper mapper = sql.getMapper(CourseMapper.class);
        List<SelectCourse> allCourse = mapper.getAllCourse();//执行并返回数据
        for (SelectCourse selectCourse : allCourse) {
            System.out.println(selectCourse.getCid()+selectCourse.getCname()+selectCourse.getTname());
        }
        sql.close();

        //打包
        Gson gson = new Gson();
        String JsonData = gson.toJson(allCourse);
        //发送
        resp.getWriter().write(JsonData);
    }

    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        doGet(req, resp);
    }
}

接收学生选课信息部分

public class StuSelectCourse extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        resp.setContentType("application/json");
        resp.setCharacterEncoding("UTF-8");
        ServletContext c = getServletContext();
        HttpSession session = req.getSession();
        String username = (String) session.getAttribute("username");
        if(username == null){
            username = (String) c.getAttribute("username");
        }

        String cid = req.getParameter("cid");
        String cname = req.getParameter("cname");
        String ct = req.getParameter("cteacher");
        System.out.println("课程号"+cid);

        //Mybatis
        SqlSession sql = MybatisUntills.getSqlSession();
        CourseMapper mapper = sql.getMapper(CourseMapper.class);
        Map<String,Object> map1 = new HashMap<String, Object>();
        map1.put("cid",cid);
        map1.put("sid",username);
        String strings = mapper.showStudentCourse(map1);
        if(strings!=null){
            resp.getWriter().write("后端返回信息：该课程已存在！");
            sql.close();
        }
        else {
            Map<String,Object> map = new HashMap<String, Object>();
            map.put("cid",cid);
            map.put("sid",username);
            int i = mapper.addStudentCourse(map);
            sql.commit();
            if(i==1){
                resp.getWriter().write("后端返回信息：选课成功！");
                System.out.println("成！");
            }
            else {
                resp.getWriter().write("后端返回信息：选课失败！");
            }
            sql.close();
        }
    }

    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        doGet(req, resp);
    }
}

2、我的课程(退课模块)

主要显示该用户选择的所有课程，并提供退课的选项，后端查询，前端显示，前端选择，后端判断，将信息返回前端

界面效果

前端源码

struct MyCourse{
  @State courses:StudentMyCourse[] = []

  aboutToAppear(){
    this.MyCourses()
  }

  build() {
    Column({ space: 5 }) {
      Text(" ")
      Row({ space: 10 }) {
        Text(" ")
        Image($r('app.media.back'))
          .width(30)
          .height(30)
          .onClick(function () {
            //返回上一页
            router.back() //直接返回
          })
        Text("我的课程")
          .fontSize(30)
          .fontWeight(FontWeight.Bolder)
      }
      .width('100%')

      Text("----------------------------------------------")
      Text(" ")
      List({space:50}){
        ForEach(
          this.courses,
          course=>{
            ListItem(){
              Row({space:30}){
                Text(" ")
                Column({space:20}){
                  Text(course.cname)
                    .fontColor(Color.Green)
                    .fontSize(15)
                    .fontWeight(FontWeight.Bolder)
                    .fontFamily("楷体")
                  Text("课程号："+course.cid)
                    .fontSize(10)
                    .fontColor(Color.Red)
                  Text("任课教师："+course.tname)
                    .fontSize(10)
                    .fontColor(Color.Green)
                  Text("上课时间："+course.ctime)
                    .fontSize(10)
                    .fontColor(Color.Green)
                }
                .justifyContent(FlexAlign.Start)
                .alignItems(HorizontalAlign.Start)
                Blank()
                Button("退课")
                  .backgroundColor(Color.Red)
                  .onClick(()=>{
                    console.log("学生点击了："+course.cname)
                    DeletCourse.STA(course.cname,course.cid,course.tname,course.ctime)
                      .then(resp=>{
                        console.log("返回成功"+resp)
                        promptAction.showToast({
                          message: resp,
                          duration: 2000,
                          bottom: 50
                        });
                      })
                  })
              }
              .width('95%')
              .height(150)
              //.padding(20)
              .backgroundColor(Color.White)
              .borderRadius(15)
              .shadow({ radius: 6, color: '#1F000000', offsetX: 2, offsetY: 4 })
            }
          }
        )
      }
      .width('100%')
    }
  }
  MyCourses(){
    GetStudentCourse.GC()
      .then(resp=>{
        console.log("返回信息成功"+resp.toString())
        if(resp.length === 0){
          promptAction.showToast({
            message: '您还没有选课哦~',
            duration: 2000,
            bottom: 50
          });
        }
        this.courses = resp
      })
  }
}

请求源码

请求所选课程

class GetStudentCourse {
  baseURL: string = IP.ip

  GC(): Promise<StudentMyCourse[]> {
    return new Promise((resolve, reject) => {
      let Http = http.createHttp()
      Http.request(
        `${this.baseURL}/GetMyCourse`,
        {
          method: http.RequestMethod.GET,
          connectTimeout: 10000,
          readTimeout: 10000
        }
      )
        .then(resp => {
          if (resp.responseCode === 200) {
            console.log("请求成功" + resp.result)
            resolve(JSON.parse(resp.result.toString()))
          }
          else {
            console.log("请求成功，但是出现问题" + resp.responseCode)
          }
        })
        .catch(error => {
          console.log("请求失败" + error)
        })
    })
  }
}

const sc = new GetStudentCourse()
export default sc as GetStudentCourse

向后端发送退课信息

class DeletCourse {

  baseURL: string = IP.ip

  STA(cname: string, cid: string, tname: string,ctime: string): Promise<string> {
    const data = {
      cname: cname,
      cid: cid,
      tname: tname,
      ctime:ctime
    }
    return new Promise((resolve, reject) => {
      let httpRequest = http.createHttp()
      httpRequest.request(
        `${this.baseURL}/DeletMyCourse`,
        {
          method: http.RequestMethod.GET,
          extraData: data,
          connectTimeout: 10000,
          readTimeout: 10000
        },
      )
        .then(resp=>{
          if(resp.responseCode===200){
            console.log("请求成功！"+resp.result)
            resolve(resp.result.toString())
          }
          else {
            console.log("请求发生错误"+resp.responseCode)
          }
        })
        .catch(err=>{
          console.log("请求失败"+err)
        })
    })
  }
}

const sc = new DeletCourse()
export default sc as DeletCourse

后端代码与选课部分相同，这里不再赘述

3、BUG修复

修复了Mybatis二级缓存溢出导致查询变慢的问题