问题
Trying to run down an error in my EF datacontext implementation that is yielding a fairly cryptic error.
Test Name: Nodes_can_be_saved
Test FullName: MyProj.Test.Integration.AFDataContextTest.Nodes_can_be_saved
Test Source: c:\Users\pvencill. \Documents\Visual Studio 2012\Projects\MyProj\MyProj.Test\Integration\AFDataContextTest.cs : line 49
Test Outcome: Failed
Test Duration: 0:00:01.4192808
Result Message:
Test method MyProj.Test.Integration.AFDataContextTest.Nodes_can_be_saved threw exception:
System.Data.Entity.Infrastructure.DbUpdateException: Error retrieving values from ObjectStateEntry. See inner exception for details. ---> System.Data.UpdateException: Error retrieving values from ObjectStateEntry. See inner exception for details. ---> System.Collections.Generic.KeyNotFoundException: The given key was not present in the dictionary.
Result StackTrace:
at System.Collections.Generic.Dictionary`2.get_Item(TKey key)
at System.Data.Mapping.ViewGeneration.Structures.MemberDomainMap.GetDomainInternal(MemberPath path)
at System.Data.Mapping.ViewGeneration.QueryRewriting.FragmentQueryKB.CreateIsOfTypeCondition(MemberPath currentPath, IEnumerable`1 derivedTypes, MemberDomainMap domainMap)
at System.Data.Mapping.ViewGeneration.QueryRewriting.FragmentQueryKB.CreateVariableConstraintsRecursion(EdmType edmType, MemberPath currentPath, MemberDomainMap domainMap, EdmItemCollection edmItemCollection)
at System.Data.Mapping.ViewGeneration.QueryRewriting.FragmentQueryKB.CreateVariableConstraintsRecursion(EdmType edmType, MemberPath currentPath, MemberDomainMap domainMap, EdmItemCollection edmItemCollection)
at System.Data.Mapping.ViewGeneration.ViewgenContext..ctor(ViewTarget viewTarget, EntitySetBase extent, IEnumerable`1 extentCells, CqlIdentifiers identifiers, ConfigViewGenerator config, MemberDomainMap queryDomainMap, MemberDomainMap updateDomainMap, StorageEntityContainerMapping entityContainerMapping)
at System.Data.Mapping.ViewGeneration.ViewGenerator.CreateViewgenContext(EntitySetBase extent, ViewTarget viewTarget, CqlIdentifiers identifiers)
at System.Data.Mapping.ViewGeneration.ViewGenerator.GenerateDirectionalViewsForExtent(ViewTarget viewTarget, EntitySetBase extent, CqlIdentifiers identifiers, KeyToListMap`2 views)
at System.Data.Mapping.ViewGeneration.ViewGenerator.GenerateDirectionalViews(ViewTarget viewTarget, CqlIdentifiers identifiers, KeyToListMap`2 views)
at System.Data.Mapping.ViewGeneration.ViewGenerator.GenerateAllBidirectionalViews(KeyToListMap`2 views, CqlIdentifiers identifiers)
at System.Data.Mapping.ViewGeneration.ViewgenGatekeeper.GenerateViewsFromCells(List`1 cells, ConfigViewGenerator config, CqlIdentifiers identifiers, StorageEntityContainerMapping containerMapping)
at System.Data.Mapping.ViewGeneration.ViewgenGatekeeper.GenerateViewsFromMapping(StorageEntityContainerMapping containerMapping, ConfigViewGenerator config)
at System.Data.Mapping.StorageMappingItemCollection.ViewDictionary.SerializedGenerateViews(StorageEntityContainerMapping entityContainerMap, Dictionary`2 resultDictionary)
at System.Data.Mapping.StorageMappingItemCollection.ViewDictionary.SerializedGetGeneratedViews(EntityContainer container)
at System.Data.Common.Utils.Memoizer`2.<>c__DisplayClass2.<Evaluate>b__0()
at System.Data.Common.Utils.Memoizer`2.Result.GetValue()
at System.Data.Common.Utils.Memoizer`2.Evaluate(TArg arg)
at System.Data.Mapping.StorageMappingItemCollection.ViewDictionary.GetGeneratedView(EntitySetBase extent, MetadataWorkspace workspace, StorageMappingItemCollection storageMappingItemCollection)
at System.Data.Mapping.Update.Internal.ViewLoader.InitializeEntitySet(EntitySetBase entitySetBase, MetadataWorkspace workspace)
at System.Data.Mapping.Update.Internal.ViewLoader.SyncInitializeEntitySet[TArg,TResult](EntitySetBase entitySetBase, MetadataWorkspace workspace, Func`2 evaluate, TArg arg)
at System.Data.Mapping.Update.Internal.ViewLoader.SyncContains[T_Element](EntitySetBase entitySetBase, MetadataWorkspace workspace, Set`1 set, T_Element element)
at System.Data.Mapping.Update.Internal.ExtractorMetadata..ctor(EntitySetBase entitySetBase, StructuralType type, UpdateTranslator translator)
at System.Data.Mapping.Update.Internal.UpdateTranslator.GetExtractorMetadata(EntitySetBase entitySetBase, StructuralType type)
at System.Data.Mapping.Update.Internal.ExtractorMetadata.ExtractResultFromRecord(IEntityStateEntry stateEntry, Boolean isModified, IExtendedDataRecord record, Boolean useCurrentValues, UpdateTranslator translator, ModifiedPropertiesBehavior modifiedPropertiesBehavior)
at System.Data.Mapping.Update.Internal.RecordConverter.ConvertStateEntryToPropagatorResult(IEntityStateEntry stateEntry, Boolean useCurrentValues, ModifiedPropertiesBehavior modifiedPropertiesBehavior)
--- End of inner exception stack trace ---
at System.Data.Mapping.Update.Internal.RecordConverter.ConvertStateEntryToPropagatorResult(IEntityStateEntry stateEntry, Boolean useCurrentValues, ModifiedPropertiesBehavior modifiedPropertiesBehavior)
at System.Data.Mapping.Update.Internal.ExtractedStateEntry..ctor(UpdateTranslator translator, IEntityStateEntry stateEntry)
at System.Data.Mapping.Update.Internal.UpdateTranslator.LoadStateEntry(IEntityStateEntry stateEntry)
at System.Data.Mapping.Update.Internal.UpdateTranslator.PullModifiedEntriesFromStateManager()
at System.Data.Mapping.Update.Internal.UpdateTranslator.ProduceCommands()
at System.Data.Mapping.Update.Internal.UpdateTranslator.Update(IEntityStateManager stateManager, IEntityAdapter adapter)
at System.Data.EntityClient.EntityAdapter.Update(IEntityStateManager entityCache)
at System.Data.Objects.ObjectContext.SaveChanges(SaveOptions options)
at System.Data.Entity.Internal.InternalContext.SaveChanges()
--- End of inner exception stack trace ---
at System.Data.Entity.Internal.InternalContext.SaveChanges()
at System.Data.Entity.Internal.LazyInternalContext.SaveChanges()
at System.Data.Entity.DbContext.SaveChanges()
at MyProj.Data.MyProjDataContext.SaveChanges() in c:\Users\pvencill. \Documents\Visual Studio 2012\Projects\MyProj\MyProj.Data\MyProjDataContext.cs:line 44
at MyProj.Test.Integration.AFDataContextTest.Nodes_can_be_saved() in c:\Users\pvencill. \Documents\Visual Studio 2012\Projects\MyProj\MyProj.Test\Integration\AFDataContextTest.cs:line 55
Researching the error led to few hits on Google, but the ones I found suggested that it's something to do w/ my model relationships, though in looking at the DB that the migrations generated, all seems in order to my eyes. My relevant models are as follows:
My data context DBSets and modelCreating definition:
public DbSet<Blip> Blips { get; set; }
public DbSet<SensorAdapter> Sensors { get; set; }
public DbSet<NodeReport> NodeReports { get; set; }
public DbSet<Node> Nodes { get; set; }
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
modelBuilder.Entity<Blip>().Property(b => b.TimeStamp).HasColumnType("datetime2");
modelBuilder.Entity<Node>().HasMany<NodeReport>(n => n.NodeReports).WithRequired(nr=>nr.Node);
modelBuilder.Entity<Blip>().HasMany<NodeReport>(b => b.NodeReports);
base.OnModelCreating(modelBuilder);
}
The Blips and SensorAdapter objects worked fine prior to adding NodeReports to them, so I suspect it's in there that the project lies.
I have a base Entity object that all my stuff inherits from, which just defines an Id property of type T; that was working fine.
NodeReport inherits from Report, whose definition is here:
public abstract class Report : Entity<long>
{
public Report()
{
Status = Status.Unknown;
}
public DateTime TimeStamp { get; set; }
public Status Status { get; set; }
public String Raw { get; set; }
}
NodeReport in turn is defined thus:
public class NodeReport : Report
{
public virtual Node Node { get; set; }
//public virtual Blip Blip { get; set; }
}
I tried it both with and without the Blip on there, commented out at the moment as I try and narrow down the problem
A Node is a fairly sparse class at hte moment too:
public class Node : Entity<long>
{
public Node ()
{
NodeReports = new List<NodeReport>();
}
public String HostName { get;set; }
public String Description { get; set; }
public virtual IList<NodeReport> NodeReports { get; set; }
}
Any suggestions would be greatly appreciated, I've been beating myself up trying to figure it.
回答1:
Well, after much searching through my code and rebuilding from scratch I found that the problem was actually that I had a derived class of Node that had a Uri as a property, which obviously failed mapping since it doesn't have a default constructor (and possibly other reasons). I solved it for now by simply changing the property to a String which I validate as a Uri internally, though I would have preferred a more elegant solution. I tried mapping Uri and even a custom subclass (w/ default constructor) of Uri to a complextype, but that didn't help.
Still, the question above is answered.
回答2:
With the @Paul's answer I could finally figure out my problem.
I am using EF with Inheritance TPT (Table per Type).
The source code
To make it easier I'll use the same classes discribed in this tutorial.
public abstract class BillingDetail
{
public int BillingDetailId { get; set; }
public string Owner { get; set; }
public string Number { get; set; }
}
[Table("BankAccounts")]
public class BankAccount : BillingDetail
{
public string BankName { get; set; }
public string Swift { get; set; }
public Agency Agency { get; set; } /* I added it */
}
public class InheritanceMappingContext : DbContext
{
public DbSet<BillingDetail> BillingDetails { get; set; }
}
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
modelBuilder.Entity<BankAccount>().ToTable("BankAccounts");
modelBuilder.Entity<CreditCard>().ToTable("CreditCards");
}
The problem
Note that I've added a new property called Agency inside the BankAccount. Given it is a complex type, if you do not map it you'll get this annoying error at runtime!
Solution
What I did was simply ignore this property Agency, but you can also map it to EF know what to do. Both will stop the error.
The most weird thing is that even not mapping the derived entity (BankAccount) the problem occurs. It seems that EF somehow knows that you created the derivation. So, if you're trying to run EF without mapping some derivation you will probably get this error too.
来源：https://stackoverflow.com/questions/13618862/entity-framework-codefirst-keynotfoundexception-in-memberdomainmap