C# 在ASP.NET中从一个表映射两个实体

我在一个图书馆管理网站上工作。作为应用程序的用户，我希望能够创建新员工，例如ceo、经理和正式员工。我已经做到了这一点，它正在发挥作用

但我希望员工能够根据各自的角色相互管理，例如，我希望：

首席执行官负责管理经理而非员工

经理管理其他经理和员工

没有人能管理首席执行官

为此，我尝试将

managerID

映射到员工id（我不知道这是否是个好主意）：

这就是我的员工控制员的样子：

@model LibraryProject.Employees

@{
    ViewBag.Title = "Create";
}

<h2>Create</h2>

@using (Html.BeginForm())
{
    @Html.AntiForgeryToken()

<div class="form-horizontal">
    <h4>Employees</h4>
    <hr />
    @Html.ValidationSummary(true, "", new { @class = "text-danger" })

    <div class="form-group">
        @Html.LabelFor(model => model.FirstName, htmlAttributes: new { @class = "control-label col-md-2" })
        <div class="col-md-10">
            @Html.EditorFor(model => model.FirstName, new { htmlAttributes = new { @class = "form-control" } })
            @Html.ValidationMessageFor(model => model.FirstName, "", new { @class = "text-danger" })
        </div>
    </div>

    <div class="form-group">
        @Html.LabelFor(model => model.LastName, htmlAttributes: new { @class = "control-label col-md-2" })
        <div class="col-md-10">
            @Html.EditorFor(model => model.LastName, new { htmlAttributes = new { @class = "form-control" } })
            @Html.ValidationMessageFor(model => model.LastName, "", new { @class = "text-danger" })
        </div>
    </div>

    <div class="form-group">
        @Html.LabelFor(model => model.Salary, htmlAttributes: new { @class = "control-label col-md-2" })
        <div class="col-md-10">
            @Html.EditorFor(model => model.Salary, new { htmlAttributes = new { @class = "form-control" } })
            @Html.ValidationMessageFor(model => model.Salary, "Your input should be an integer between 1-10.", new { @class = "text-danger" })
        </div>
    </div>

    <div class="form-group">
        @Html.LabelFor(model => model.IsCEO, htmlAttributes: new { @class = "control-label col-md-2" })
        <div class="col-md-10">
            <div class="checkbox">
                @Html.EditorFor(model => model.IsCEO)
                @Html.ValidationMessageFor(model => model.IsCEO, "", new { @class = "text-danger" })
            </div>
        </div>
    </div>

    <div class="form-group">
        @Html.LabelFor(model => model.IsManager, htmlAttributes: new { @class = "control-label col-md-2" })
        <div class="col-md-10">
            <div class="checkbox">
                @Html.EditorFor(model => model.IsManager)
                @Html.ValidationMessageFor(model => model.IsManager, "", new { @class = "text-danger" })
            </div>
        </div>
    </div>

    <div class="form-group">
        @Html.LabelFor(model => model.ManagerId, htmlAttributes: new { @class = "control-label col-md-2" })
        <div class="col-md-10">
            @Html.EditorFor(model => model.ManagerId, new { htmlAttributes = new { @class = "form-control" } })
            @Html.ValidationMessageFor(model => model.ManagerId, "", new { @class = "text-danger" })
        </div>
    </div>

    <div class="form-group">
        <div class="col-md-offset-2 col-md-10">
            <input type="submit" value="Create" class="btn btn-default" />
        </div>
    </div>
</div>
}

<div>
    @Html.ActionLink("Back to List", "Index")
</div>

@section Scripts {
    @Scripts.Render("~/bundles/jqueryval")
}

@using (Html.BeginForm())
{
    if (!string.IsNullOrEmpty(ViewBag.ErrorMessage5))
    {
        <div>
            <p>

                <span style="color:red;">@ViewBag.ErrorMessage5</span>

            </p>
        </div>
    }
    <div class="form-horizontal" />
}

using System;
using System.Collections.Generic;
using System.Data;
using System.Data.Entity;
using System.Linq;
using System.Net;
using System.Web;
using System.Web.Mvc;
using LibraryProject;

namespace LibraryProject.Controllers
{
    public class EmployeesController : Controller
    {
        private LibraryDbEntities db = new LibraryDbEntities();

        // GET: Employees
        public ActionResult Index()
        {
            // Linq queries to show all the employees separately, is used to not mixed them up.
            var getCeo = from employeCEO in db.Employees 
                         where employeCEO.IsCEO == true 
                         select employeCEO;
          
            var getEmployee = from employee in db.Employees 
                              where employee.IsCEO == false && employee.IsManager == false  
                              select employee;
           
            var getManager = from employeeManager in db.Employees 
                             where employeeManager.IsManager == true && employeeManager.IsCEO == false  
                             select employeeManager;

            IEnumerable<Employees> list = getCeo.Concat(getEmployee).Concat(getManager);
           
            return View(list.ToList());
        }

        public ActionResult CEO()
        {
           // linq query used to display ceo in a separate view
            var getCeo = from employeCEO in db.Employees  
                         where employeCEO.IsCEO == true 
                         select employeCEO;
            return View(getCeo);
        }

        public ActionResult TheManager()
        {
            // linq query used to display manager in a separate view
            var getManager = from employeeManager in db.Employees 
                             where employeeManager.IsManager == true && employeeManager.IsCEO == false 
                             select employeeManager;
            return View(getManager);
        }

        public ActionResult RegularEmployee()
        {
            // linq query used to display employee in a separate view
            var getEmployee = from employee in db.Employees 
                              where employee.IsCEO == false && employee.IsManager == false 
                              select employee;
            return View(getEmployee);
        }

        // GET: Employees/Details/5
        public ActionResult Details(int? id)
        {
            if (id == null)
            {
                return new HttpStatusCodeResult(HttpStatusCode.BadRequest);
            }

            Employees employees = db.Employees.Find(id);

            if (employees == null)
            {
                return HttpNotFound();
            }

            return View(employees);
        }

        // GET: Employees/Create
        public ActionResult Create()
        {
            ViewBag.Employees = new SelectList(db.Category, "Id", "Employees");
            return View();
        }

        // POST: Employees/Create
        // To protect from overposting attacks, enable the specific properties you want to bind to, for 
        // more details see https://go.microsoft.com/fwlink/?LinkId=317598.
        [HttpPost]
        [ValidateAntiForgeryToken]
        public ActionResult Create([Bind(Include = "Id,FirstName,LastName,Salary,IsCEO,IsManager,ManagerId")] Employees employees)
        {
            if (ModelState.IsValid)
            {
                //salary coefficient for the employees
                decimal salaryCeo = 2.725M;
                decimal salaryManager = 1.725M;
                decimal employeeSalary = 1.125M;

                var ceo = db.Employees.Count(x => x.IsCEO == true);

                //Checks if there is a ceo
                if (ceo == 0)
                {
                    employees.Salary = employees.Salary * salaryCeo; // calculate ceo salary

                    db.Employees.Add(employees);
                    db.SaveChanges();

                    return RedirectToAction("Index");
                } 
                else if (ceo == 1 && employees.IsCEO == true) // check if there is a ceo, if yes show errormessage
                {
                    ViewBag.ErrorMessage5 = "There is already a CEO in the database! You cannot create a second one!";
                } 
                else if(employees.IsCEO == false && employees.IsManager == false) // check if the employee is ceo or manager, if false its a regular employee
                {
                    employees.Salary = employees.Salary * employeeSalary; // calculate regular employees salary
                    db.Employees.Add(employees);
                    db.SaveChanges();
                    return RedirectToAction("Index");
                }
                else if (employees.IsCEO == false && employees.IsManager == true) // manager
                {
                    employees.Salary = employees.Salary * salaryManager; // manager salary
                    db.Employees.Add(employees);
                    db.SaveChanges();
                    return RedirectToAction("Index");
                }
            }

            return View(employees);
        }

        // GET: Employees/Edit/5
        public ActionResult Edit(int? id)
        {
            if (id == null)
            {
                return new HttpStatusCodeResult(HttpStatusCode.BadRequest);
            }

            Employees employees = db.Employees.Find(id);

            if (employees == null)
            {
                return HttpNotFound();
            }

            return View(employees);
        }

        // POST: Employees/Edit/5
        // To protect from overposting attacks, enable the specific properties you want to bind to, for 
        // more details see https://go.microsoft.com/fwlink/?LinkId=317598.
        [HttpPost]
        [ValidateAntiForgeryToken]
        public ActionResult Edit([Bind(Include = "Id,FirstName,LastName,Salary,IsCEO,IsManager,ManagerId")] Employees employees)
        {
            if (ModelState.IsValid)
            {
                db.Entry(employees).State = EntityState.Modified;
                db.SaveChanges();
                return RedirectToAction("Index");
            }
            return View(employees);
        }

        // GET: Employees/Delete/5
        public ActionResult Delete(int? id)
        {
            if (id == null)
            {
                return new HttpStatusCodeResult(HttpStatusCode.BadRequest);
            }

            Employees employees = db.Employees.Find(id);

            if (employees == null)
            {
                return HttpNotFound();
            }

            return View(employees);
        }

        // POST: Employees/Delete/5
        [HttpPost, ActionName("Delete")]
        [ValidateAntiForgeryToken]
        public ActionResult DeleteConfirmed(int id)
        {
            Employees employees = db.Employees.Find(id);
            db.Employees.Remove(employees);
            db.SaveChanges();
            return RedirectToAction("Index");
        }

        protected override void Dispose(bool disposing)
        {
            if (disposing)
            {
                db.Dispose();
            }
            base.Dispose(disposing);
        }
    }
}

使用系统；
使用System.Collections.Generic；
使用系统数据；
使用System.Data.Entity；
使用System.Linq；
Net系统；
使用System.Web；
使用System.Web.Mvc；
利用图书馆项目；
命名空间LibraryProject.Controllers
{
公共类EmployeesController:控制器
{
私有LibraryDbEntities db=新的LibraryDbEntities（）；
//获取：员工
公共行动结果索引（）
{
//Linq查询单独显示所有员工，用于不混淆他们。
var getCeo=来自db.Employees中的Employeeceo
其中employeCEO.IsCEO==true
选择employeeceo；
var getEmployee=来自db.Employees中的雇员
其中employee.IsCEO==false&&employee.IsManager==false
选择员工；
var getManager=来自数据库employeeManager.Employees
其中employeeManager.IsManager==true&&employeeManager.IsCEO==false
选择员工经理；
IEnumerable list=getCeo.Concat（getEmployee.Concat（getManager）；
返回视图（list.ToList（））；
}
公共行动结果首席执行官（）
{
//用于在单独视图中显示ceo的linq查询
var getCeo=来自db.Employees中的Employeeceo
其中employeCEO.IsCEO==true
选择employeeceo；
返回视图（getCeo）；
}
公共行动结果经理（）
{
//用于在单独视图中显示管理器的linq查询
var getManager=来自数据库employeeManager.Employees
其中employeeManager.IsManager==true&&employeeManager.IsCEO==false
选择员工经理；
返回视图（getManager）；
}
公共行动结果正规员工（）
{
//用于在单独视图中显示员工的linq查询
var getEmployee=来自db.Employees中的雇员
其中employee.IsCEO==false&&employee.IsManager==false
选择员工；
返回视图（getEmployee）；
}
//获取：员工/详细信息/5
公共行动结果详细信息（int？id）
{
if（id==null）
{
返回新的HttpStatusCodeResult（HttpStatusCode.BadRequest）；
}
Employees=db.Employees.Find（id）；
if（employees==null）
{
返回HttpNotFound（）；
}
返回视图（员工）；
}
//获取：员工/创建
公共操作结果创建（）
{
ViewBag.Employees=新的选择列表（db.Category，“Id”，“Employees”）；
返回视图（）；
}
//职位：员工/创建
//若要防止套印攻击，请启用要绑定到的特定属性，例如
//更多详细信息请参见https://go.microsoft.com/fwlink/?LinkId=317598.
[HttpPost]
[ValidateAntiForgeryToken]
公共操作结果创建（[Bind（Include=“Id，FirstName，LastName，Salary，IsCEO，IsManager，ManagerId”）]Employees）
{
if（ModelState.IsValid）
{
//员工工资系数
十进制工资CEO=2.725M；
十进制工资经理=1.725M；
十进制员工工资=1.125米；
var ceo=db.Employees.Count（x=>x.IsCEO==true）；
//检查是否有ceo
如果（ceo==0）
{
employees.Salary=employees.Salary*salaryCeo；//计算ceo薪资
db.Employees.Add（员工）；
db.SaveChanges（）；
返回操作（“索引”）；
} 
else if（ceo==1&&employees.IsCEO==true）//检查是否有ceo，如果是，则显示错误消息
{
ViewBag.ErrorMessage5=“数据库中已经有一个CEO！您不能创建第二个！”；
} 
else if（employees.IsCEO==false&&employees.IsManager==false）//检查该员工是否为ceo或经理，如果为false，则检查其是否为普通员工
{
employees.Salary=employees.Salary*employeeSalary；//计算普通员工工资
db.Employees.Add（员工）；
db.SaveChanges（）；
返回操作（“索引”）；
}
else if（employees.IsCEO==false&&employees.IsManager==true）//manager
{
employees.Salary=employees.Salary*salaryManager；//经理薪资
db.Employees.Add（员工）；
db.SaveChanges（）；
返回操作（“索引”）；
}
}
返回视图（员工）；
}
//获取：雇员/编辑/5
公共行动结果编辑（int？id）
{
if（id==null）
{
using System;
using System.Collections.Generic;
using System.Data;
using System.Data.Entity;
using System.Linq;
using System.Net;
using System.Web;
using System.Web.Mvc;
using LibraryProject;

namespace LibraryProject.Controllers
{
    public class EmployeesController : Controller
    {
        private LibraryDbEntities db = new LibraryDbEntities();

        // GET: Employees
        public ActionResult Index()
        {
            // Linq queries to show all the employees separately, is used to not mixed them up.
            var getCeo = from employeCEO in db.Employees 
                         where employeCEO.IsCEO == true 
                         select employeCEO;
          
            var getEmployee = from employee in db.Employees 
                              where employee.IsCEO == false && employee.IsManager == false  
                              select employee;
           
            var getManager = from employeeManager in db.Employees 
                             where employeeManager.IsManager == true && employeeManager.IsCEO == false  
                             select employeeManager;

            IEnumerable<Employees> list = getCeo.Concat(getEmployee).Concat(getManager);
           
            return View(list.ToList());
        }

        public ActionResult CEO()
        {
           // linq query used to display ceo in a separate view
            var getCeo = from employeCEO in db.Employees  
                         where employeCEO.IsCEO == true 
                         select employeCEO;
            return View(getCeo);
        }

        public ActionResult TheManager()
        {
            // linq query used to display manager in a separate view
            var getManager = from employeeManager in db.Employees 
                             where employeeManager.IsManager == true && employeeManager.IsCEO == false 
                             select employeeManager;
            return View(getManager);
        }

        public ActionResult RegularEmployee()
        {
            // linq query used to display employee in a separate view
            var getEmployee = from employee in db.Employees 
                              where employee.IsCEO == false && employee.IsManager == false 
                              select employee;
            return View(getEmployee);
        }

        // GET: Employees/Details/5
        public ActionResult Details(int? id)
        {
            if (id == null)
            {
                return new HttpStatusCodeResult(HttpStatusCode.BadRequest);
            }

            Employees employees = db.Employees.Find(id);

            if (employees == null)
            {
                return HttpNotFound();
            }

            return View(employees);
        }

        // GET: Employees/Create
        public ActionResult Create()
        {
            ViewBag.Employees = new SelectList(db.Category, "Id", "Employees");
            return View();
        }

        // POST: Employees/Create
        // To protect from overposting attacks, enable the specific properties you want to bind to, for 
        // more details see https://go.microsoft.com/fwlink/?LinkId=317598.
        [HttpPost]
        [ValidateAntiForgeryToken]
        public ActionResult Create([Bind(Include = "Id,FirstName,LastName,Salary,IsCEO,IsManager,ManagerId")] Employees employees)
        {
            if (ModelState.IsValid)
            {
                //salary coefficient for the employees
                decimal salaryCeo = 2.725M;
                decimal salaryManager = 1.725M;
                decimal employeeSalary = 1.125M;

                var ceo = db.Employees.Count(x => x.IsCEO == true);

                //Checks if there is a ceo
                if (ceo == 0)
                {
                    employees.Salary = employees.Salary * salaryCeo; // calculate ceo salary

                    db.Employees.Add(employees);
                    db.SaveChanges();

                    return RedirectToAction("Index");
                } 
                else if (ceo == 1 && employees.IsCEO == true) // check if there is a ceo, if yes show errormessage
                {
                    ViewBag.ErrorMessage5 = "There is already a CEO in the database! You cannot create a second one!";
                } 
                else if(employees.IsCEO == false && employees.IsManager == false) // check if the employee is ceo or manager, if false its a regular employee
                {
                    employees.Salary = employees.Salary * employeeSalary; // calculate regular employees salary
                    db.Employees.Add(employees);
                    db.SaveChanges();
                    return RedirectToAction("Index");
                }
                else if (employees.IsCEO == false && employees.IsManager == true) // manager
                {
                    employees.Salary = employees.Salary * salaryManager; // manager salary
                    db.Employees.Add(employees);
                    db.SaveChanges();
                    return RedirectToAction("Index");
                }
            }

            return View(employees);
        }

        // GET: Employees/Edit/5
        public ActionResult Edit(int? id)
        {
            if (id == null)
            {
                return new HttpStatusCodeResult(HttpStatusCode.BadRequest);
            }

            Employees employees = db.Employees.Find(id);

            if (employees == null)
            {
                return HttpNotFound();
            }

            return View(employees);
        }

        // POST: Employees/Edit/5
        // To protect from overposting attacks, enable the specific properties you want to bind to, for 
        // more details see https://go.microsoft.com/fwlink/?LinkId=317598.
        [HttpPost]
        [ValidateAntiForgeryToken]
        public ActionResult Edit([Bind(Include = "Id,FirstName,LastName,Salary,IsCEO,IsManager,ManagerId")] Employees employees)
        {
            if (ModelState.IsValid)
            {
                db.Entry(employees).State = EntityState.Modified;
                db.SaveChanges();
                return RedirectToAction("Index");
            }
            return View(employees);
        }

        // GET: Employees/Delete/5
        public ActionResult Delete(int? id)
        {
            if (id == null)
            {
                return new HttpStatusCodeResult(HttpStatusCode.BadRequest);
            }

            Employees employees = db.Employees.Find(id);

            if (employees == null)
            {
                return HttpNotFound();
            }

            return View(employees);
        }

        // POST: Employees/Delete/5
        [HttpPost, ActionName("Delete")]
        [ValidateAntiForgeryToken]
        public ActionResult DeleteConfirmed(int id)
        {
            Employees employees = db.Employees.Find(id);
            db.Employees.Remove(employees);
            db.SaveChanges();
            return RedirectToAction("Index");
        }

        protected override void Dispose(bool disposing)
        {
            if (disposing)
            {
                db.Dispose();
            }
            base.Dispose(disposing);
        }
    }
}