【发布时间】：2013-12-29 00:42:59
【问题描述】：
我有一个使用实体框架的 MVC3 应用程序。我已经有大约一年没有使用这个应用程序了。最近，我在一台新 PC 上打开它并尝试在调试模式下运行并在调试中点击以下异常/堆栈跟踪。主要的例外似乎是“无法将文件附加为数据库”和“底层提供程序在打开时失败”。我在堆栈溢出时搜索了这些错误，我发现的答案似乎与这种情况不匹配。例如，“无法将文件附加为数据库”的答案之一表明旧版本的数据库可能位于本地数据库上，但是当我浏览到 localdb 时，我在本地数据库中看不到任何数据库在视觉工作室。
我正在寻找有关接下来要调查什么以解决此问题的指导。有什么建议吗？
实际失败的代码是：
var currentHunt = (from ph in this.repo.GetAllPuzzleHunts()
orderby ph.PuzzleHuntId descending
select ph).FirstOrDefault();
这是网络应用第一次尝试通过实体框架从数据库中获取数据。
FWIW 这台机器有 Entity Framework 6.0，我使用的是 Visual Studio 2012。
异常/堆栈跟踪如下：
System.Data.DataException was unhandled by user code
HResult=-2146233087
Message=An exception occurred while initializing the database. See the InnerException for details.
Source=EntityFramework
StackTrace:
at System.Data.Entity.Internal.InternalContext.PerformInitializationAction(Action action)
at System.Data.Entity.Internal.InternalContext.PerformDatabaseInitialization()
at System.Data.Entity.Internal.LazyInternalContext.<InitializeDatabase>b__4(InternalContext c)
at System.Data.Entity.Internal.RetryAction`1.PerformAction(TInput input)
at System.Data.Entity.Internal.LazyInternalContext.InitializeDatabaseAction(Action`1 action)
at System.Data.Entity.Internal.LazyInternalContext.InitializeDatabase()
at System.Data.Entity.Internal.InternalContext.Initialize()
at System.Data.Entity.Internal.InternalContext.GetEntitySetAndBaseTypeForType(Type entityType)
at System.Data.Entity.Internal.Linq.InternalSet`1.Initialize()
at System.Data.Entity.Internal.Linq.InternalSet`1.GetEnumerator()
at System.Data.Entity.Infrastructure.DbQuery`1.System.Collections.Generic.IEnumerable<TResult>.GetEnumerator()
at System.Linq.Buffer`1..ctor(IEnumerable`1 source)
at System.Linq.OrderedEnumerable`1.<GetEnumerator>d__0.MoveNext()
at System.Linq.Enumerable.FirstOrDefault[TSource](IEnumerable`1 source)
at GutolMvcApp.Controllers.HomeController.Index() in c:\Users\jordanat\Documents\Visual Studio 2012\Projects\Gutol\Gutol\GutolMvcApp\Controllers\HomeController.cs:line 25
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.Async.AsyncControllerActionInvoker.<>c__DisplayClass42.<BeginInvokeSynchronousActionMethod>b__41()
at System.Web.Mvc.Async.AsyncResultWrapper.<>c__DisplayClass8`1.<BeginSynchronous>b__7(IAsyncResult _)
at System.Web.Mvc.Async.AsyncResultWrapper.WrappedAsyncResult`1.End()
at System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeActionMethod(IAsyncResult asyncResult)
at System.Web.Mvc.Async.AsyncControllerActionInvoker.<>c__DisplayClass37.<>c__DisplayClass39.<BeginInvokeActionMethodWithFilters>b__33()
at System.Web.Mvc.Async.AsyncControllerActionInvoker.<>c__DisplayClass4f.<InvokeActionMethodFilterAsynchronously>b__49()
InnerException: System.Data.Entity.Core.EntityException
HResult=-2146233087
Message=The underlying provider failed on Open.
Source=EntityFramework
StackTrace:
at System.Data.Entity.Core.EntityClient.EntityConnection.Open()
at System.Data.Entity.Core.Objects.ObjectContext.EnsureConnection()
at System.Data.Entity.Core.Objects.ObjectContext.ExecuteInTransaction[T](Func`1 func, IDbExecutionStrategy executionStrategy, Boolean startLocalTransaction, Boolean releaseConnectionOnSuccess)
at System.Data.Entity.Core.Objects.ObjectQuery`1.<>c__DisplayClassb.<GetResults>b__9()
at System.Data.Entity.SqlServer.DefaultSqlExecutionStrategy.Execute[TResult](Func`1 operation)
at System.Data.Entity.Core.Objects.ObjectQuery`1.GetResults(Nullable`1 forMergeOption)
at System.Data.Entity.Core.Objects.ObjectQuery`1.<System.Collections.Generic.IEnumerable<T>.GetEnumerator>b__0()
at System.Lazy`1.CreateValue()
at System.Lazy`1.LazyInitValue()
at System.Lazy`1.get_Value()
at System.Data.Entity.Internal.LazyEnumerator`1.MoveNext()
at System.Linq.Enumerable.FirstOrDefault[TSource](IEnumerable`1 source)
at System.Data.Entity.Core.Objects.ELinq.ObjectQueryProvider.<GetElementFunction>b__1[TResult](IEnumerable`1 sequence)
at System.Data.Entity.Core.Objects.ELinq.ObjectQueryProvider.ExecuteSingle[TResult](IEnumerable`1 query, Expression queryRoot)
at System.Data.Entity.Core.Objects.ELinq.ObjectQueryProvider.System.Linq.IQueryProvider.Execute[TResult](Expression expression)
at System.Data.Entity.Internal.Linq.DbQueryProvider.Execute[TResult](Expression expression)
at System.Linq.Queryable.FirstOrDefault[TSource](IQueryable`1 source)
at System.Data.Entity.Internal.EdmMetadataRepository.QueryForModelHash(Func`2 createContext)
at System.Data.Entity.Internal.InternalContext.QueryForModelHash()
at System.Data.Entity.Internal.ModelCompatibilityChecker.CompatibleWithModel(InternalContext internalContext, ModelHashCalculator modelHashCalculator, Boolean throwIfNoMetadata)
at System.Data.Entity.Internal.InternalContext.CompatibleWithModel(Boolean throwIfNoMetadata)
at System.Data.Entity.Database.CompatibleWithModel(Boolean throwIfNoMetadata)
at System.Data.Entity.CreateDatabaseIfNotExists`1.InitializeDatabase(TContext context)
at System.Data.Entity.Internal.InternalContext.<>c__DisplayClasse`1.<CreateInitializationAction>b__d()
at System.Data.Entity.Internal.InternalContext.PerformInitializationAction(Action action)
InnerException: System.Data.SqlClient.SqlException
HResult=-2146232060
Message=Cannot attach the file 'C:\Users\...\Visual Studio 2012\Projects\Gutol\Gutol\GutolMvcApp\App_Data\PuzzleCollateral.mdf' as database 'PuzzleCollateral'.
感谢您的帮助！
【问题讨论】：
标签： asp.net-mvc-3 entity-framework visual-studio-debugging localdb