EF Core 中的 modelBuilder.Configurations.AddFromAssembly

Question

在EntityFramework 6.x 中，如果我们有很多EntityConfiguration 类，那么我们可以将它们全部分配在OnModelCreating(ModelBuilder modelBuilder) 中，如下所示，而不是一一分配：

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

   modelBuilder.Configurations.AddFromAssembly(typeof(MyDbContext).Assembly);
}

有没有类似 modelBuilder.Configurations.AddFromAssembly 在 Entity Framework Core.

Answer 1

对于 EF Core

你可以写一个扩展方法如下：

public static class ModelBuilderExtensions
{
    public static void ApplyAllConfigurations(this ModelBuilder modelBuilder)
    {
        var typesToRegister = Assembly.GetExecutingAssembly().GetTypes().Where(t => t.GetInterfaces()
            .Any(gi => gi.IsGenericType && gi.GetGenericTypeDefinition() == typeof(IEntityTypeConfiguration<>))).ToList();

        foreach (var type in typesToRegister)
        {
            dynamic configurationInstance = Activator.CreateInstance(type);
            modelBuilder.ApplyConfiguration(configurationInstance);
        }
    }
}

然后在OnModelCreating如下：

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

   modelBuilder.ApplyAllConfigurations();
}

对于 EF Core >= 2.2

从 EF Core 2.2 开始，您无需编写任何自定义扩展方法。 EF Core 2.2 为此添加了ApplyConfigurationsFromAssembly 扩展方法。您可以按如下方式使用它：

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

   modelBuilder.ApplyConfigurationsFromAssembly(typeof(UserConfiguration).Assembly); // Here UseConfiguration is any IEntityTypeConfiguration
}

谢谢。