Entity Framework Code First and Multiple Assemblies
I have a subclass in a different assembly to its base class. The parent is a POCO class used for EF Code First.
When I try to add an instance of inherited class to the database I get InvalidOperationException: "Object mapping could not be found for Type with identity 'Foo.Bar.My开发者_JAVA技巧InheritedClass'".
It works fine if subclass is in same assembly as base class.
In regular EF the solution seems to be a call to ObjectContext.MetadataWorkspace.LoadFromAssembly(assembly). But I can't figure out how this relates to Code First.
Any advice?
I'm using Entity Framework 4.1 RC.
I solved this by inheriting from the first assembliy's DbContext, adding a DbSet<> for the derived class, and then adding new instances of derived type to to that.
Posted code on MSDN forum here.
I know this post is a bit old, but I was able to accomplish this using @Dave's recomendation inside the constructor:
public Context() {
((IObjectContextAdapter)this).ObjectContext.MetadataWorkspace.LoadFromAssembly(
System.Reflection.Assembly.GetAssembly(
typeof(--[Inherited DbContext]--)));
}
I'm quite new to EF (Entity Framework 4) and I got the same exception when I made changes in the model.
My problem turned out to be that I did not know EF need all the names on all the navigation properties to agree, not only their type. For example if there is a navigation property named foo, then there needs to be a declared variable in the corresponding class with the very same name.
精彩评论