Entity Framework Code First - Configuration in another file

Question

What is the best way to separate the mapping of tables to entities using the Fluent API so that it is all in a separate class and not inline in the OnModelCreating method?

What I am doing currently:

public class FooContext : DbContext {
    // ...
    protected override OnModelCreating(DbModelBuilder modelBuilder) {
        modelBuilder.Entity<Foo>().Property( ... );
        // ...
    }
}

What i want:

public class FooContext : DbContext {
    // ...
    protected override OnModelCreating(DbModelBuilder modelBuilder) {
        modelBuilder.LoadConfiguration(SomeConfigurationBootstrapperClass);
    }
}

How do you do this? I am using C#.

Answer 1

You will want to create a class that inherits from the EntityTypeConfiguration class, like so:

public class FooConfiguration : EntityTypeConfiguration<Foo>
{
    public FooConfiguration()
    {
        // Configuration goes here...
    }
}

Then you can load the configuration class as part of the context like so:

public class FooContext : DbContext
{
    protected override OnModelCreating(DbModelBuilder modelBuilder)
    {
        modelBuilder.Configurations.Add(new FooConfiguration());
    }
}

This article goes into greater detail on using configuration classes.