EF Core Mapping EntityTypeConfiguration

Question

In EF6 we usually able to use this way to configure the Entity.

public class AccountMap : EntityTypeConfiguration
{
    public AccountMap()
           


        

Answer 1

You can achieve this through some simple additional types:

internal static class ModelBuilderExtensions
{
   public static void AddConfiguration(
     this ModelBuilder modelBuilder, 
     DbEntityConfiguration entityConfiguration) where TEntity : class
   {     
       modelBuilder.Entity(entityConfiguration.Configure);
   }
}

internal abstract class DbEntityConfiguration where TEntity : class
{     
    public abstract void Configure(EntityTypeBuilder entity);
}

Usage:

internal class UserConfiguration : DbEntityConfiguration
{
    public override void Configure(EntityTypeBuilder entity)
    {
        entity.ToTable("User");
        entity.HasKey(c => c.Id);
        entity.Property(c => c.Username).HasMaxLength(255).IsRequired();
        // etc.
    }
}

protected override void OnModelCreating(ModelBuilder modelBuilder)
{
    base.OnModelCreating(modelBuilder);

    modelBuilder.AddConfiguration(new UserConfiguration());
}