MVC TO LINQ

        //
        // GET: /Home/
        TestTryEntities Db = new TestTryEntities();

        public ActionResult Index()
        {
            return View();
        }

        /// <summary>
        /// 查询
        /// </summary>
        /// <returns></returns>
        public ActionResult GetStudent()
        {
            int pageIndex = 1;//页码
            int pageSize = 10;//每页条数
            //var data = Db.Student.OrderBy(r => r.ID)
            //    .Skip(pageSize * (pageIndex - 1)).Take(pageSize)
            //    .Select(r => new { r.ID, r.Name, r.Password });

            var data1 = (from r in Db.Student
                         join t in Db.Class on r.ClassID equals t.ID
                         orderby r.ID
                         select new { r.ID, r.Name, r.Password, t.ClassName })
                         .Skip(pageSize * (pageIndex - 1)).Take(pageSize);

            int total = Db.Student.Count();//总条数
            //构造成Json的格式传递


            var result = new { total = total, rows = data1 };
            return Json(result, JsonRequestBehavior.AllowGet);
        }

        //添加
        public ActionResult Add()
        {
            var data = Db.Class.Select(r => new SelectListItem()
            {
                Text = r.ClassName,
                Value = SqlFunctions.StringConvert((double)r.ID)
            }).ToList();

            ViewData["Class"] = data;
            return View();

        }
        [HttpPost]
        public ActionResult Add(Model.Student model)
        {
            Db.Student.Add(model);
            Db.SaveChanges();
            return View("Index");
        }

        /// <summary>
        /// 修改
        /// </summary>
        /// <param name="ID"></param>
        /// <returns></returns>
        public ActionResult Edit(int ID)
        {
            var model = Db.Student.Where(r => r.ID == ID).Select(r => r).FirstOrDefault();
            ViewData["modelStudent"] = model;


            var data = Db.Class.Select(r => new SelectListItem()
            {
                Text = r.ClassName,
                Value = SqlFunctions.StringConvert((double)r.ID),
                Selected = (r.ID == model.ClassID)
            }).ToList();
            ViewData["Class"] = data;
            return View(model);
        }

        [HttpPost]
        public ActionResult Edit(Model.Student model)
        {
            Db.Student.Attach(model);
            Db.Entry<Student>(model).State = System.Data.EntityState.Modified;
            
            if (Db.SaveChanges() > 0)
            {
                return Content("OK");
            }
            else
            {
                return Content("修改失败");
            }
        }

        /// <summary>
        /// 删除
        /// </summary>
        /// <param name="ID"></param>
        /// <returns></returns>
        public ActionResult Delete(int ID)
        {
            //var model = Db.Student.Where(r => r.ID == ID).Select(r => r).FirstOrDefault();
            //if (model == null)
            //{
            //  return Script("alert('验证失败！)");
            //  return View("Index");
            //}
            //Db.Student.Remove(model);
            //Db.SaveChanges();

            var model1 = new Model.Student() { ID = ID };
            if (model1 == null)
            {
                return View("Index");
            }
            Db.Student.Attach(model1);
            Db.Entry<Student>(model1).State = System.Data.EntityState.Deleted;
            Db.SaveChanges();

            return View("Index");
        }

        public ActionResult AddMulti()
        {


            return View();
        }

        [HttpPost]
        public ActionResult AddMulti(Mvctry.Models.ClassStudent model)
        {


            return View();
        }
    }