一、课程列表后端实现

1、定义搜索对象

CourseQuery

package com.guli.edu.query;
@ApiModel(value = "Course查询对象", description = "课程查询对象封装")
@Data
public class CourseQuery implements Serializable {
    private static final long serialVersionUID = 1L;
    @ApiModelProperty(value = "课程名称")
    private String title;
    @ApiModelProperty(value = "讲师id")
    private String teacherId;
    @ApiModelProperty(value = "一级类别id")
    private String subjectParentId;
    @ApiModelProperty(value = "二级类别id")
    private String subjectId;
}

2、定义service方法

接口

void pageQuery(Page<Course> pageParam, CourseQuery courseQuery);

实现

@Override
public void pageQuery(Page<Course> pageParam, CourseQuery courseQuery) {
    QueryWrapper<Course> queryWrapper = new QueryWrapper<>();
    queryWrapper.orderByDesc("gmt_create");
    if (courseQuery == null){
        baseMapper.selectPage(pageParam, queryWrapper);
        return;
    }
    String title = courseQuery.getTitle();
    String teacherId = courseQuery.getTeacherId();
    String subjectParentId = courseQuery.getSubjectParentId();
    String subjectId = courseQuery.getSubjectId();
    if (!StringUtils.isEmpty(title)) {
        queryWrapper.like("title", title);
    }
    if (!StringUtils.isEmpty(teacherId) ) {
        queryWrapper.eq("teacher_id", teacherId);
    }
    if (!StringUtils.isEmpty(subjectParentId)) {
        queryWrapper.ge("subject_parent_id", subjectParentId);
    }
    if (!StringUtils.isEmpty(subjectId)) {
        queryWrapper.ge("subject_id", subjectId);
    }
    baseMapper.selectPage(pageParam, queryWrapper);
}

3、定义web层方法

@ApiOperation(value = "分页课程列表")
@GetMapping("{page}/{limit}")
public R pageQuery(
        @ApiParam(name = "page", value = "当前页码", required = true)
        @PathVariable Long page,
        @ApiParam(name = "limit", value = "每页记录数", required = true)
        @PathVariable Long limit,
        @ApiParam(name = "courseQuery", value = "查询对象", required = false)
                CourseQuery courseQuery){
    Page<Course> pageParam = new Page<>(page, limit);
    courseService.pageQuery(pageParam, courseQuery);
    List<Course> records = pageParam.getRecords();
    long total = pageParam.getTotal();
    return  R.ok().data("total", total).data("rows", records);
}

二、课程列表前端实现

1、定义api

course.js

getPageList(page, limit, searchObj) {
  return request({
    url: `${api_name}/${page}/${limit}`,
    method: 'get',
    params: searchObj
  })
},

三、课程删除后端实现

1、web层

定义删除api方法：CourseAdminController.java

@ApiOperation(value = "根据ID删除课程")
@DeleteMapping("{id}")
public R removeById(
    @ApiParam(name = "id", value = "课程ID", required = true)
    @PathVariable String id){
    boolean result = courseService.removeCourseById(id);
    if(result){
        return R.ok();
    }else{
        return R.error().message("删除失败");
    }
}

2、service层

如果用户确定删除，则首先删除video记录，然后删除chapter记录，最后删除Course记录

2.1、在VideoService中定义根据courseId删除video业务方法

接口

boolean removeByCourseId(String courseId);

实现

@Override
public boolean removeByCourseId(String courseId) {
    QueryWrapper<Video> queryWrapper = new QueryWrapper<>();
    queryWrapper.eq("course_id", courseId);
    Integer count = baseMapper.delete(queryWrapper);
    return null != count && count > 0;
}

2.2、在ChapterService中定义根据courseId删除chapter业务方法

接口

boolean removeByCourseId(String courseId);

实现

@Override
public boolean removeByCourseId(String courseId) {
    QueryWrapper<Chapter> queryWrapper = new QueryWrapper<>();
    queryWrapper.eq("course_id", courseId);
    Integer count = baseMapper.delete(queryWrapper);
    return null != count && count > 0;
}

2.3、删除当前course记录

接口：CourseService.java

boolean removeCourseById(String id);

实现：CourseServiceImpl.java

@Override
public boolean removeCourseById(String id) {
    //根据id删除所有视频
    videoService.removeByCourseId(id);
    //根据id删除所有章节
    chapterService.removeByCourseId(id);
    Integer result = baseMapper.deleteById(id);
    return null != result && result > 0;
}

二、课程删除前端实现

1、定义api

course.js中添加删除方法

removeById(id) {
    return request({
        url: `${api_name}/${id}`,
        method: 'delete'
    })
}