c# - 实体框架 - 代码优先 - 与共享主键的一对多关系

Question

任何人都知道如何使用 EF Code First Fluent API 实现此场景：

public class Referancial
{
    // Identity
    public int KeyID { get; set; }

    public string Code { get; set; }

    public virtual ICollection<Translation> Translations { get; set; }

}

public class Translation
{
    // refer to Referancial.KeyID
    public int KeyID { get; set; }

    public int LanguageID { get; set; }

    public string Label { get; set; }

}

谢谢您的答复

Answer 1

尝试其他型号，我认为它更适合您

public class Referancial
{
    // Identity
    public int KeyID { get; set; }

    public string Code { get; set; }

    public virtual ICollection<Translation> Translations { get; set; }

}

public class Translation
{
    //Translation needs its own Key
    public int ID { get; set; }
    // reference directly the Referencial object instead of the ID
    public Referencial Referencial { get; set; }

    public int LanguageID { get; set; }

    public string Label { get; set; } 
}

配置您的模型

_modelBuilder.Entity<Referancial>().HasKey(r => r.KeyID);
_modelBuilder.Entity<Translation>().HasKey(t => t.ID);
_modelBuilder.Entity<Referancial>().HasMany(r => r.Translations).WithRequired(t => t.Referencial).WillCascadeOnDelete(true);

Answer 2

//关于模型创建：

受保护的覆盖无效 OnModelCreating(DbModelBuilder modelBuilder) {

        // Person

        modelBuilder.Entity<Person>().HasKey(e => e.PersonID)
                                     .ToTable("Persons")
                                     .Property(e => e.PersonID)
                                     .HasDatabaseGeneratedOption(DatabaseGeneratedOption.Identity);


        //Referancial
        modelBuilder.Entity<Referancial>().HasKey(e => e.KeyID)
                                          .ToTable("Referancials")
                                          .Property(e => e.KeyID)
                                          .HasDatabaseGeneratedOption(DatabaseGeneratedOption.Identity);


        //Translation
        modelBuilder.Entity<Translation>().ToTable("Translations")
                                          .HasKey(e => e.KeyID)
                                          .Property(e => e.KeyID)
                                          .HasDatabaseGeneratedOption(DatabaseGeneratedOption.None);


        modelBuilder.Entity<Referancial>()
                    .HasOptional(e=>e.Translations)
                    .WithMany()
                    .HasForeignKey(e => e.KeyID);

        base.OnModelCreating(modelBuilder);
    }

但它给我一个错误：

在模型生成期间检测到一个或多个验证错误：

PersonSearch.Models.Referancial_Translations：：多重性与关系“Referancial_Translations”中角色“Referancial_Translations_Target”中的引用约束冲突。因为从属角色中的所有属性都不可为空，所以主体角色的多重性必须为“1”。Referancial_Translations_Source：：多重性在关系“Referancial_Translations”中的角色“Referancial_Translations_Source”中无效。因为从属角色指的是关键属性，所以从属角色的多重性的上限必须是“1”。