Using phantom key types with EF Code First 4.3

Question

Is it possible to use phantom types with Code First for my primary key?

I have something like this:

class Id<TEntity, TKey>
   where TEntity : Entity
{
   // implementation
}

class Entity<TEntity, TKey> {
   [Key]
   public Id<MyEntity, Guid> Id { get; set; }
}

class MyEntity : Entity<MyEntity, Guid> {

}

What do you mean by "phantom types" ? the only mentions of them I found were in relation to functional languages... — Thomas Levesque, Feb 13 '12 at 00:05
@ThomasLevesque - see this question http://stackoverflow.com/questions/5881301/implementing-phantom-types-in-c-sharp — Daniel A. White, Feb 13 '12 at 00:16

score 2 · Answer 1 · answered Feb 13 '12 at 00:24

2

No. EF has a predefined set of allowed data types for properties. And it only knows how to convert these types to database types and back. There is not mechanism to implement custom type converters either in EF. nHibernate may allow this.

answered Feb 13 '12 at 00:24

Eranga

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Using phantom key types with EF Code First 4.3

1 Answers1