用同样的标识值不同的对象已经与会话+ NHibernate的

Question

我使用ninject MVC 3和NHibernate和我得到这个错误，当我尝试做一个更新，我不明白为什么有关。

NHibernate.NonUniqueObjectException was unhandled by user code 
    Message=a different object with the same identifier value was already associated with the session: e1a7bd1f-fe1d-4c2e-a459-9fcb0106ad1d, of entity: Card 
    Source=NHibernate 
    EntityName=Card 
    StackTrace: 
     at NHibernate.Engine.StatefulPersistenceContext.CheckUniqueness(EntityKey key, Object obj) 
     at NHibernate.Event.Default.DefaultSaveOrUpdateEventListener.PerformUpdate(SaveOrUpdateEvent event, Object entity, IEntityPersister persister) 
     at NHibernate.Event.Default.DefaultSaveOrUpdateEventListener.EntityIsDetached(SaveOrUpdateEvent event) 
     at NHibernate.Event.Default.DefaultUpdateEventListener.PerformSaveOrUpdate(SaveOrUpdateEvent event) 
     at NHibernate.Event.Default.DefaultSaveOrUpdateEventListener.OnSaveOrUpdate(SaveOrUpdateEvent event) 
     at NHibernate.Impl.SessionImpl.FireUpdate(SaveOrUpdateEvent event) 
     at NHibernate.Impl.SessionImpl.Update(Object obj) 
     at CCRecomendator.Framework.Data.Repository.NhibernateRepo.Update[T](T entity) in NhibernateRepo.cs:line 33 
     at CardService.EditCard(Card card, IList`1 rewardTiersToUseAfterCap) in CardService.cs:line 108 
     at 
    CardController.EditCbCreditCard(CbCreditCardFrmVm vm) in CardController.cs:line 505 
     at lambda_method(Closure , ControllerBase , Object[]) 
     at System.Web.Mvc.ActionMethodDispatcher.Execute(ControllerBase controller, Object[] parameters) 
     at System.Web.Mvc.ReflectedActionDescriptor.Execute(ControllerContext controllerContext, IDictionary`2 parameters) 
     at System.Web.Mvc.ControllerActionInvoker.InvokeActionMethod(ControllerContext controllerContext, ActionDescriptor actionDescriptor, IDictionary`2 parameters) 
     at System.Web.Mvc.ControllerActionInvoker.<>c__DisplayClass15.<InvokeActionMethodWithFilters>b__12() 
     at System.Web.Mvc.ControllerActionInvoker.InvokeActionMethodFilter(IActionFilter filter, ActionExecutingContext preContext, Func`1 continuation) 
    InnerException: 

我不明白为什么它仍然会在nhibernate会话。我有一个Web请求获取该卡并将其绑定到VM。

然后显示在页面上。然后我有一个被调用的保存方法，我尝试将虚拟机绑定到卡域，然后尝试更新它，这是当我得到上述错误。

这些是虽然2个不同的呼叫和会话应当丢弃掉。

Bind<ISessionFactory>().ToProvider<NhibernateSessionFactoryProvider>().InSingletonScope(); 
      Bind<ISession>().ToMethod(context => context.Kernel.Get<ISessionFactory>().OpenSession()).InRequestScope(); 

我不确定是否需要调用另一个dispose或什么。

我用工作单位，所以我说Dispose方法，但不知道什么时候我应该怎么称呼它，如果这甚至会解决我的问题

public class UnitOfWork : IUnitOfWork, IDisposable 
    { 
     private ITransaction transaction; 
     private readonly ISession session; 

     public UnitOfWork(ISession session) 
     { 
      this.session = session; 
      session.FlushMode = FlushMode.Auto; 
     } 

     /// <summary> 
     /// Starts a transaction with the database. Uses IsolationLevel.ReadCommitted 
     /// </summary> 
     public void BeginTransaction() 
     { 
      transaction = session.BeginTransaction(IsolationLevel.ReadCommitted); 
     } 

     /// <summary> 
     /// starts a transaction with the database. 
     /// </summary> 
     /// <param name="level">IsolationLevel the transaction should run in.</param> 
     public void BeginTransaction(IsolationLevel level) 
     { 
      transaction = session.BeginTransaction(level); 
     } 

     private bool IsTransactionActive() 
     { 
      return transaction.IsActive; 
     } 

     /// <summary> 
     /// Commits the transaction and writes to the database. 
     /// </summary> 
     public void Commit() 
     { 
      // make sure a transaction was started before we try to commit. 
      if (!IsTransactionActive()) 
      { 
       throw new InvalidOperationException("Oops! We don't have an active transaction. Did a rollback occur before this commit was triggered: " 
                  + transaction.WasRolledBack + " did a commit happen before this commit: " + transaction.WasCommitted); 
      } 

      transaction.Commit(); 
     } 

     /// <summary> 
     /// Rollback any writes to the databases. 
     /// </summary> 
     public void Rollback() 
     { 
      if (IsTransactionActive()) 
      { 
       transaction.Rollback(); 
      } 
     } 

     public void Dispose() // don't know where to call this to see if it will solve my problem 
     { 
      if (session.IsOpen) 
      { 
       session.Close(); 
      } 

     } 


[HttpPost] 
public ActionResult EditCbCard(CbCardFrmVm vm) 
{ 
    if (ModelState.IsValid) 
    { 
     Card card = new Card 
     { 
      Id = vm.Id, // id of the record in the database 
      Country = countryService.LoadCountryById(vm.SelectedCountry) 
     }; 

     CardService.EditCard(card, rewardTiersToUseAfterCap); 

    } 

    ModelStateValidationWrapper wrapper = ConvertTo.ModelStateValidationWrapper(creditCardService.ValidationDictionary, ModelState); 
    return Json(wrapper); 
} 

    public void EditCard(Card card, IList<string> rewardTiersToUseAfterCap) 
    { 
     try 
     { 
      unitOfWork.BeginTransaction(); 

      nhibernateRepo.Update(creditCard); 

      unitOfWork.Commit(); 
     } 
     catch (ADOException ex) 
     { 
      ErrorSignal.FromCurrentContext().Raise(ex); 
      ValidationDictionary.AddError("DbError", ExceptionMsgs.DbError); 
      unitOfWork.Rollback(); 
     } 
     catch (SqlException ex) 
     { 
      ErrorSignal.FromCurrentContext().Raise(ex); 
      ValidationDictionary.AddError("DbError", ExceptionMsgs.DbError); 
      unitOfWork.Rollback(); 
     } 
    } 

任何人都明白为什么它会认为这是在同会话。

Answer 1

即使你处理这将是不正确的创建一个新的卡更新状态的会话。取而代之的

Card card = new Card 
{ 
    Id = vm.Id, // id of the record in the database 
    Country = countryService.LoadCountryById(vm.SelectedCountry) 
}; 

使用

Card card = unitOfWork.Get<Card>(vm.Id) 
card.Country = countryService.LoadCountryById(vm.SelectedCountry); 

，以获得正确的状态。它会给你的缓存实例可用时没有击中数据库