如何在gorm中获取struct（内部struct）值

我是Golang和GORM的新手 . 我有一些问题 . 我怎样才能获得内部结构值？ （就像golang中的嵌套结构一样），我试过但是，我没有得到实际的结果 .

我有三个结构

Department Struct

type Department struct {
    gorm.Model
    DepartmentName string
    DeptCode       string
    Employee       Employee //Employee struct
}

Employee struct

type Employee struct {
    gorm.Model
    EmpId           string
    EmpName         string
    DepartmentID    uint //Department id
    EmployeeContact []EmployeeContact //Array of Employee contact
}

Employee Contact

type EmployeeContact struct {
    gorm.Model
    ContactType string
    ContacText  string
    EmployeeID  uint //Employee Id
}

Relationship

#Department是员工的父母 .

#Employee是员工联系人的父母 .

我用了GORM（加入）

var departmentStruct model.Department
var employeeStruct model.Employee

    db.Debug().Model(&departmentStruct).Joins("JOIN employees ON employees.department_id = departments.id").Joins("JOIN employee_contacts ON employee_contacts.employee_id = employees.id").Select("employees.id,departments.department_name,departments.dept_code,employees.emp_id,employees.emp_name,employee_contacts.contact_type").Scan(&employeeStruct)
    res1B, _ := json.Marshal(employeeStruct)
    fmt.Fprintln(w, string(res1B))

它将返回 output

{

    "ID":1,
    "EmpId":"001",
    "EmpName":"samsung",
    "DepartmentID":0, 
    "EmployeeContact":{ //It will be return empty
        "ID":0,
        "CreatedAt":"0001-01-01T00:00:00Z",
        "UpdatedAt":"0001-01-01T00:00:00Z",
        "DeletedAt":null,
        "ContactType":"",
        "ContacText":"",
        "EmployeeID":0
    }

}

我需要，当我通过Employee id 时，它会像下面给出的格式一样返回

{

    "ID":1,
    "EmpId":"001",
    "EmpName":"samsung",
    "Department":{
        "ID":1,
        "CreatedAt":"0001-01-01T00:00:00Z",
        "UpdatedAt":"0001-01-01T00:00:00Z",
        "DeletedAt":null,
        "DepartmentName":"Software Analyst",
        "deptCode":"SA"
    },
    "EmployeeContact":[
        {
            "ID":1,
            "CreatedAt":"0001-01-01T00:00:00Z",
            "UpdatedAt":"0001-01-01T00:00:00Z",
            "DeletedAt":null,
            "ContactType":"Home",
            "ContacText":"1234567890",
            "EmployeeID":1
        },
        {
            "ID":2,
            "CreatedAt":"0001-01-01T00:00:00Z",
            "UpdatedAt":"0001-01-01T00:00:00Z",
            "DeletedAt":null,
            "ContactType":"Office",
            "ContacText":"0123456789",
            "EmployeeID":1
        }
    ]
}

任何人都可以教我吗？我怎样才能实现它 . 谢谢 .