c# - Entity Framework - 重用复杂类型

Question

我在 Code First Entity Framework 中有一个实体，目前看起来像这样:

public class Entity
{
    // snip ...

    public string OriginalDepartment { get; set; }
    public string OriginalQueue { get; set; }

    public string CurrentDepartment { get; set; }
    public string CurrentQueue { get; set; }
}

我想像这样为这些类型创建复杂类型:

public class Location
{
    public string Department { get; set; }
    public string Queue { get; set; }
}

我想对 Current 和 Original 使用相同的类型:

public Location Original { get; set; }
public Location Current { get; set; }

这可能吗，还是我需要创建两个复杂类型 CurrentLocation 和 OriginalLocation？

public class OriginalLocation
{
    public string Department { get; set; }
    public string Queue { get; set; }
}

public class CurrentLocation
{
     public string Department { get; set; }
     public string Queue { get; set; }
}

Answer 1

开箱即用，您无需创建两个复杂类型。

您还可以使用模型构建器显式配置复杂类型

modelBuilder.ComplexType<Location>();

要自定义列名，您应该从父实体配置中配置它们

public class Location
{
    public string Department { get; set; }
    public string Queue { get; set; }
}

public class MyEntity
{
    public int Id { get; set; }
    public Location Original { get; set; }
    public Location Current { get; set; }
}

public class MyDbContext : DbContext
{
    protected override void OnModelCreating(DbModelBuilder modelBuilder)
    {
        modelBuilder.ComplexType<Location>();

        modelBuilder.Entity<MyEntity>().Property(x => x.Current.Queue).HasColumnName("myCustomColumnName");
    }
}

这会将 MyEntity.Current.Queue 映射到 myCustomName 列