MVC3和MVC4中CRUD操作

public class HomeController : Controller
{
//
// GET: /Home/
CarModelContainer db = new CarModelContainer();

#region 查询所有 +Index()
public ActionResult Index()
{

List<CarModel> list = (from c in db.CarModel select c).ToList();
//ViewData["DataList"] = list;  上下两种效果一样  都是为了传递数据到前台
return View(list);   //这样传输的是强类型的数据 在前台通过Model获取
}
#endregion

#region 添加信息 +Create()

[HttpGet]
public ActionResult Create()
{
return View();
}
[HttpPost]
public ActionResult Create(CarModel car)
{
if (ModelState.IsValid)   //后台的验证信息
{
db.CarModel.AddObject(car);
db.SaveChanges();
return RedirectToAction("Index");

}
else
{
return View(car);
}

}
#endregion

#region 编辑信息 +Edit()
[HttpGet]
public ActionResult Edit(int id)
{
CarModel car=(from a in db.CarModel
where a.ID==id
select a).FirstOrDefault();

if (car==null)
{
return RedirectToAction("Index");

}
return View(car);
}
[HttpPost]
public ActionResult Edit(CarModel car)
{
try
{
//第一种方式  使用LinQ查询出要编辑的对象
//CarModel model=(from a in db.CarModel
//          where a.ID==car.ID
//          select a).FirstOrDefault();

//第二种方式  创建一个所以要添加的对象 car中的实体属性 系统会自动检索得到对应的值
CarModel model = new CarModel() { ID=car.ID};
db.CarModel.Attach(model);

UpdateModel(model);
db.SaveChanges();
return RedirectToAction("index");
}
catch (Exception )
{
ModelState.AddModelError("","修改失败，请查看详细错误信息");

}
return View(car);

}

#endregion

#region 删除信息 +Delete()
public ActionResult Delete(int id)
{
CarModel car = (from a in db.CarModel
where a.ID == id
select a).FirstOrDefault();
db.CarModel.DeleteObject(car);
db.SaveChanges();
return RedirectToAction("index");
}
#endregion

}

//添加实体
public bool AddEntity(Model.Customer entity)
{
Hotel.Model.HotelModelContainer db = new Model.HotelModelContainer();
db.Customer.Add(entity);
int count = db.SaveChanges();
if (count > 0)
{
return true;
}
return false;

}
//删除实体
public bool DeleteEntity(Model.Customer entity)
{
Hotel.Model.HotelModelContainer db = new Model.HotelModelContainer();
Customer cus = db.Customer.Where<Customer>(c => c.ID == entity.ID).FirstOrDefault<Customer>();
if (cus != null)
{
db.Customer.Remove(cus);

}
int count = db.SaveChanges();
if (count > 0)
{
return true;
}
return false;
}
//更新实体
public bool UpdateEntity(Model.Customer entity)
{
Hotel.Model.HotelModelContainer db = new Model.HotelModelContainer();
// DbEntityEntry<Customer> entry = db.Entry<Customer>(entity);
//entry.State = System.Data.EntityState.Unchanged;
//entry.Property("CustomerName").IsModified = true;
// entry.Property("Phone").IsModified = true;</span>
db.Entry(entity).State = EntityState.Modified;
int count = db.SaveChanges();
if (count > 0)
{
return true;
}
return false;

}

//查询数据
public IQueryable<Model.Customer> LoadEntities(Func<Model.Customer, bool> whereLambda)
{
HotelModelContainer db = new HotelModelContainer();
return db.Customer.Where<Customer>(whereLambda).AsQueryable<Customer>();
}
//查询分页数据并排序
public IQueryable<Customer> LoadPageEntities<s>(Func<Customer, bool> whereLambda, int pageSize, int pageIndex, out int totalCount, Func<Customer, s> orderByLambda)
{
HotelModelContainer db = new HotelModelContainer();
totalCount = db.Customer.Where<Customer>(whereLambda).Count();
IQueryable<Customer> customers = db.Customer.Where<Customer>(whereLambda)
.OrderBy<Customer, s>(orderByLambda)
.Skip<Customer>(pageSize * (pageIndex - 1))
.Take<Customer>(pageSize)
.AsQueryable<Customer>();
return customers;
}
//按照编号删除
public bool DeleteEntity(object Id)
{
Hotel.Model.HotelModelContainer db = new Model.HotelModelContainer();
Customer cus = db.Customer.Where<Customer>(c => c.ID == (int)Id).FirstOrDefault<Customer>();
if (cus != null)
{
db.Customer.Remove(cus);

}
int count = db.SaveChanges();
if (count > 0)
{
return true;
}
return false;
}