public class UpdateHelp:IDisposable    {//记录已经复制过的实体类，避免重复加载        private IList<Type> listType = new List<Type>();private BusinessContext _context;

public UpdateHelp(BusinessContext context)        {            _context = context;        }

public void Dispose()        {            _context.Dispose();        }

//更新普通属性        private void CloneProperty(PropertyInfo propertyInfo,object intrinsicObj,object newObj)        {var data = propertyInfo.GetValue(newObj, null);            propertyInfo.SetValue(intrinsicObj, data, null);        }

//更新普通导航属性        private void CloneNavigationProperty(PropertyInfo propertyInfo,object intrinsicObj,object newObj)        {var data = propertyInfo.GetValue(newObj, null);object dataClone = UpdateIntrinsticObj(data);            propertyInfo.SetValue(intrinsicObj, dataClone, null);        }

//更新返回值为集合EntityCollection<TEntity>的导航属性        private void CloneNavigationPropertyEntityCollection(PropertyInfo propertyInfo, object intrinsicObj, object newObj)        {//获取参数newObj中的对象集合            IEnumerable<object> newData = propertyInfo.GetValue(newObj, null) as IEnumerable<object>;//获取上下文中匹配的原对象集合            var intrinsicData = propertyInfo.GetValue(intrinsicObj, null);//利用EntityCollection<TEntity>类的扩展方法Add在原集合中加入新对象            var addMethod = intrinsicData.GetType().GetMethod("Add");foreach (object obj in newData)            {                Object objClone = UpdateIntrinsticObj(obj);                addMethod.Invoke(intrinsicData, new object[] { objClone });            }        }

//获取上下文中待更新的原对象        private object GetIntrinsicObj(EntityObject entity)        {                        Object intrinsicObj;//根据输入对象的EntityKey判断该对象是已有值还是新建值//若是已有值即从上下文中获取对应值，若是新建值即反射生成一个新对象            if (entity.EntityKey.EntityKeyValues != null)                intrinsicObj = _context.GetObjectByKey(entity.EntityKey);else                intrinsicObj = Activator.CreateInstance(entity.GetType());

return intrinsicObj;        }

//更新上下文中的原对象，返回值为更新后的原对象        public object UpdateIntrinsticObj(Object obj)        {//记录已经复制过的实体类，避免重复加载            listType.Add(obj.GetType());//获取上下文中的原对象            Object intrinsicObj=GetIntrinsicObj(obj as EntityObject);//更新原对象的每个一个属性//把原对象intrinsicObj的每一个属性设置为与obj对象相等            foreach (PropertyInfo propertyInfo in obj.GetType().GetProperties())            {//若listType里面包含些类型，证明此实体类已经更新过                if (!listType.Contains(propertyInfo.PropertyType) && propertyInfo.CanWrite                    && propertyInfo.Name != "EntityKey"&& propertyInfo.PropertyType.Name != "EntityReference`1")                {//若为导航属性则需要使用此方法更新                    if (propertyInfo.GetCustomAttributes(typeof(EdmRelationshipNavigationPropertyAttribute), false).Count() != 0)                    {//若导航属性返回值为集合则使用此方法                        if (propertyInfo.PropertyType.Name == "EntityCollection`1")                            CloneNavigationPropertyEntityCollection(propertyInfo, intrinsicObj, obj);else//若导航属性为普通对象则使用以下方法                            CloneNavigationProperty(propertyInfo, intrinsicObj, obj);                    }else //若为普通属性则使用以下方法                        CloneProperty(propertyInfo, intrinsicObj, obj);                }            }return intrinsicObj;        }    }

    public class LinqHelp:IDisposable    {private BusinessContext _context;private UpdateHelp _updateHelp;

public LinqHelp()        {            _context = new BusinessContext();            _updateHelp = new UpdateHelp(_context);        }

public LinqHelp(BusinessContext context)        {            _context = context;            _updateHelp = new UpdateHelp(context);        }

public void Dispose()        {            _context.Dispose();        }

public int Add<T>(T entity) where T : EntityObject        {int n = -1;            Transaction transaction = Transaction.Current;try            {                _context.AddObject(entity.GetType().Name, entity);                n = _context.SaveChanges();            }catch (Exception ex)            {                Business.Common.ExceptionManager.DataException.DealWith(ex);                transaction.Rollback();            }return n;        }

public int Update<T>(ref T entity) where T:EntityObject        {int n = -1;            Transaction transaction = Transaction.Current;try            {                EntityObject returnObj = this._updateHelp.UpdateIntrinsticObj(entity) as EntityObject;                n = _context.SaveChanges();                entity = _context.GetObjectByKey(entity.EntityKey) as T;            }catch (Exception ex)            {                Business.Common.ExceptionManager.DataException.DealWith(ex);                transaction.Rollback();            }return n;        }

public List<T> GetList<T>(string name) where T:EntityObject        {......}         ........    }

public class OrderRepository    {private LinqHelp _linqHelp;

public OrderRepository()        {            _linqHelp = new LinqHelp();         }

public int AddOrder(Order order)        {..........}

        ..............

public int UpdateOrder(Order order)        {return _linqHelp.Update<Order>(ref order);        }    }

    public class PersonRepository    {......}

class Program    {static void Main(string[] args)        {            Test1();            Console.ReadKey();        }

public static void Test1()        {using (BusinessContext context = new BusinessContext())            {                context.ContextOptions.LazyLoadingEnabled = true;var order = context.Order.First();                order.Person.Address = "北京路1号";                OrderRepository orderRepository = new OrderRepository();                orderRepository.UpdateOrder(order);            }        }

        public static void Test2()        {            using (BusinessContext context = new BusinessContext())            {                Person person = context.Person.First();                Order order = new Order();                order.OrderNumber = "2A34313344";                OrderItem orderItem = new OrderItem();                orderItem.Goods = "555";                orderItem.Count = 8;                orderItem.Price = 2.5;                order.OrderItem.Add(orderItem);                person.Order.Add(order);

                PersonRepository personRepository = new PersonRepository();                personRepository.UpdatePerson(person);                Console.Write(person.Order.First().ID + person.Order.First().OrderItem.First().ID);            }        }    }