问题
I have two Entity Data models within a MVC3 project A and B.
I have recently added the new entity data model B to deal with some new functionality, the issue is that now the existing code has stopped working and I am getting the following error when trying to access code within entity model A.
The error message is:
Could not find the conceptual model type 'project.models.Bclass'
I do not understand why it is this new functionality has affected the current code seeing as entity model A has not change in any way. And functionality B is in a separate class and does not interfere with model A.
When the new code is removed from the project and entity model B is excluded then the code works as it should.
Here is some of the stacktrace from the error:
Exception : Could not find the conceptual model type for 'Project1.Models.CrossSession'.
Application Class - method : System.Data.Metadata.Edm.MetadataWorkspace -- GetEdmSpaceType
User : temp.user
Url : http://localhost/project1/auth/message
Stacktrace : at System.Data.Metadata.Edm.MetadataWorkspace.GetEdmSpaceType(StructuralType objectSpaceType)
at System.Data.Entity.Internal.InternalContext.UpdateEntitySetMappings()
at System.Data.Entity.Internal.InternalContext.TryUpdateEntitySetMappingsForType(Type entityType)
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.get_InternalContext()
回答1:
Solution found. It appears in some cases (randomly) there is a mix up in the code generated by the entity framework. This is apparently a known bug and a fix should be coming in future releases. In the mean time the way around this is to move the efm to a separate class within the solution.
回答2:
Solved this by updating EntityFramework to the latest version (6.0) http://nuget.org/packages/EntityFramework/.
After installing it regenerate the models and it will work ;)
回答3:
I had the same problem with 2 different .edmx files in the same project.
For the first .edmx model I had used "Add Code Generation Item", for the second model I hadn't. The project was building correctly but throwing that exception on runtime.
I solved generating the .tt classes for the second .edmx model as well.
回答4:
One possible explanation is that if you use the database first approach and forget to add the Entity classes, you will get this error.
i.e. (from the guide linked below)
- Right click on the model’s designer surface.
- From the context menu, choose Add Code Generation Item.
- In the Add New Item dialog that opens, select Data from the list of installed templates types on the left.
- Choose the ADO.NET DbContext Generator then click the Add button.
I normally use Julie Lerman's guide; https://msdn.microsoft.com/en-us/library/jj206878(v=vs.113).aspx
回答5:
Well I just installed EF 4.1 and tried to combine DbContext with a EMDX - When I tried to pass back a view I got the same error - that's why I ended up here... I think the way around this is to separate the functionality out into separate asemblies in the solution...
回答6:
This can also be resolved by generating the new edmx in visual studio 2010 so it matches the older ones... (And copying over the files it generates)
回答7:
Using Visual Studio 12, the issue has still not been resolved. As an alternative workaround, I set up the second SQL data model using "old fashioned" Data Classes that pre-date entity models - they're still there and they still work. Use Add - New Item - (Data Category) - LINQ To SQL Classes, open the ServerExplorer, locate the server and database, then drag and drop it onto the data classes pane. Old school - but conveniently overcomes this highly inconvenient issue when the full functionality of entity models is not needed.
回答8:
I removed the edmx models, removed the Entity package, re-install the entity 5.0 and works.
来源：https://stackoverflow.com/questions/8974973/could-not-find-the-conceptual-model-type