若依框架——＞三级联动 添加，默认修改

add.html

			学校:
			

				
					请选择学校
				
			
		
		

			年级:
			

				
					请选择年级
				
			
		
		

			班级:
			

				
					请选择班级
				
			
		

js

$(document).ready(function() {   //页面加载时运行此函数  放在最前端
		/* 三级联动 */
		$.ajax({
			url: ctx + "system/school/select",
			type: 'GET',
			success:function (data) {
				
				$("#aschool").empty();
				
				$("#aschool").append("请选择学校");
				
				for (var i = 0; i < data.length; i++){
					$("#aschool").append("" + data[i].sname + "");
				}
			}
		});
		$("#aschool").change(function () {//同上面一样
			// alert($("#aschool").val())
			$.ajax({
				url: ctx + "system/grade/select",
				type: 'GET',
				data: {
					scid: $("#aschool").val(),
				},
				success:function (data) {
					$("#agrade").empty();
					$("#agrade").append("请选择年级");
					for (var i = 0; i < data.length; i++){
						$("#agrade").append("" + data[i].gname + "");
					}
				}
			});
		});
	$("#agrade").change(function () {//同上面一样
			// alert($("#agrade").val())
			$.ajax({
				url: ctx + "system/classes/select",
				type: 'GET',
				data: {
					gid: $("#agrade").val(),
				},
				success:function (data) {
					$("#aclasses").empty();
					$("#aclasses").append("请选择班级");
					for (var i = 0; i < data.length; i++){
						$("#aclasses").append("" + data[i].cname + "");
					}
				}
			})
		});
	});

Service层

GradelService

 /* 三级联动 */
public List selectGradeBid1(Integer scid);

ClassesService

//联动
public List selectClassBid1(Integer gid);

Controller层

SchoolController 最高层

	/* 三级联动 */
    @GetMapping("/select")
    @ResponseBody
    public List select(){
        List list1 = aschoolService.selectSchoolList(new GXSchool());
        return  list1;
    }

GradeController

/* 三级联动 */
@GetMapping("/select")
@ResponseBody
public List select(Integer scid){
    List list1 = gradeService.selectGradeBid1(scid);
    return  list1;
}

ClassesController

/* 联动 */
@GetMapping("/select")
@ResponseBody
public List select(Integer gid){
    List list1 = classesService.selectClassBid1(gid);
    return  list1;
}

ClassesMapper.xml

    
    where aclass.gid = #{aclasses.gid}

GradeMapper.xml

 

    
    where agrade.scid = #{scid}

默认修改

edit.html

            学生学校：
            

                
                    请选择学校
                    
                
            
        
        

            学生年级：
            

                
                    请选择年级
                    
                
            
        
        

            学生班级：
            

                
                    请选择班级
                    
                
            
        

js

//联动修改默认
$(document).ready(function () {
    //获取controller层的函数，进行默认选中
    var gid = [[${gradeId}]];
    var scid = [[${schoolId}]];

    $("#agrade").val(gid);
        // alert(gid);
    $("#aschool").val(scid);
},

    $("#aschool").change(function () {//同上面一样
        $.ajax({
            url: ctx + "system/grade/select",
            type: 'GET',
            data: {
                gid: $("#aschool").val(),
            },
            success:function (data) {
                $("#agrade").empty();
                $("#agrade").append("请选择");
                for (var i = 0; i < data.length; i++){
                    $("#agrade").append("" + data[i].gname + "");
                }
            }
        })
    }),
    $("#agrade").change(function () {//同上面一样
            $.ajax({
                url: ctx + "system/classes/select",
                type: 'GET',
                data: {
                    gid: $("#agrade").val(),
                },
                success:function (data) {
                    $("#aclasses").empty();
                    $("#aclasses").append("请选择班级");
                    for (var i = 0; i < data.length; i++){
                        $("#aclasses").append("" + data[i].cname + "");
                    }
                },
            })
    }),
)

StudentController

@GetMapping("/edit/{id}")
public String edit(@PathVariable("id") int id, ModelMap mmap){
    mmap.put("student", studentService.selectStudentById(id));
    mmap.put("school",schoolService.selectSchoolList(new GXSchool()));
    mmap.put("grade",gradeService.selectGradeList(new GXGrade()));
    //通过id进行判断并且取值，通过id进行逐层查询获取id，先向上准确查询，在向下模糊查询，默认选中在下面。
    String classes1= studentService.selectStudentById(id).getCid();
    String grade1 = classesService.selectClassesByCid(Integer.parseInt(classes1)).getGid();
    int school1 = gradeService.selectGradeBygid(Integer.parseInt(grade1)).getScid();

    mmap.put("classId",classes1);
    mmap.put("gradeId",grade1);
    mmap.put("schoolId",school1);

    mmap.put("Grade", gradeService.selectGradeBid1(school1));
    mmap.put("Classes", classesService.selectClassBid1(Integer.parseInt(grade1)));
    return prefix + "/edit";
}