Fluent Nhibernate 多对多问题

Question

我有三张桌子：

1. 人员（ID、名字）
2. 组织（ID、名称）
3. PersonOrganization（PersonId、OrganizationId、Details）多对多表

当我第一次使用 Fluent NHibernate 进行映射时，我在 PersonOrganization 表中没有详细信息列，而是在 PersonMap 和 OrganizationMap 中使用 HasManyToMany 进行映射（无需创建 PersonOrganization 域对象或映射）。我可以写如下代码：

Organization org = new Organization { Name = "org" };
People people = new People { FirstName = "firstname", Organization = org };

peopleRepository.Add(people);          // ISession.Save(people)
unitOfWork.Commit();                   // ITransaction.Commit()

NHhibernate 愉快地将数据提交到所有三个表。

当我在 PersonOrganization 表中添加详细信息列时，问题出现了。经过一番研究，我现在必须创建一个新的 PersonOrganization 域对象，并为 Person 和 Organization 映射和设置 HasMany 关系。我更新的模型和地图如下：

public class People
{
    public People()
    {
        LinkToOrganization = new List<PeopleOrganization>();
    }

    public virtual int Id { get; set; }
    public virtual string FirstName { get; set; }
    public virtual IList<PeopleOrganization> LinkToOrganization { get; set; }
}

public class Organization
{
    public Organization()
    {
        LinkToPeople = new List<PeopleOrganization>();
    }

    public virtual int Id { get; set; }
    public virtual string Name { get; set; }
    public virtual IList<PeopleOrganization> LinkToPeople { get; set; }
}

public class PeopleOrganization
{
    public virtual People People { get; set; }
    public virtual Organization Organization { get; set; }
    public virtual string Details { get; set; }
}

public class PeopleMap : ClassMap<People>
{
    public PeopleMap()
    {
        Id(p => p.Id);
        Map(p => p.FirstName).Length(100);

        HasMany(x => x.LinkToOrganization)
            .Table("PeopleOrganization")
            .KeyColumn("PeopleId")
            .AsBag()
            .Inverse();
    }
}

public class OrganizationMap : ClassMap<Organization>
{
    public OrganizationMap()
    {
        Id(p => p.Id);
        Map(p => p.Name).Length(50);

        HasMany(x => x.LinkToPeople)
            .Table("PeopleOrganization")
            .KeyColumn("OrganizationId")
            .AsBag()
            .Inverse();
    }
}

public class PeopleOrganizationMap : ClassMap<PeopleOrganization>
{
    public PeopleOrganizationMap()
    {
        CompositeId()
            .KeyReference(p => p.People, "PeopleId")
            .KeyReference(p => p.Organization, "OrganizationId");

        Map(p => p.Details).Length(100);
    }
}

我现在必须编写以下代码：

People people = new People { FirstName = "firstname" };
Organization org = new Organization { Name = "org" };
PeopleOrganization po = new PeopleOrganization { People = people, Organization = org, Details = "details" };

peopleRepository.Add(people);          // ITransaction.Begin() ISession.Save(people)
organizationRepository.Add(org);       // ISession.Save(org)
peopleOrganizationRepository.Add(po);  // ISession.Save(po)

unitOfWork.Commit();                   // ITransaction.Commit()

我的问题是：

1. 我的映射是否正确设置为支持这种多对多场景？
2. 是否有办法让我能够执行以下操作（这将写入所有三个表）：

-

People people = new People { FirstName = "firstname" };
Organization org = new Organization { Name = "org" };
PeopleOrganization po = new PeopleOrganization { People = people, Organization = org, Details = "details" };

peopleRepository.Add(people);          // Just ONE ISession.Save(people)

unitOfWork.Commit();                   // ITransaction.Commit()

非常感谢您的任何意见。

谢谢

Answer 1

首先，您需要将新创建的 PeopleOrganization 添加到两个实体（Organization 和 People）的集合中。然后，如果您将Cascade.All() 添加到您的HasMany 链中，则保存应该传播（级联）到PeopleOrganization，随后传播到Organization。

作为纯粹的语义建议，我建议将 PeopleOrganization 创建封装到 Person 上的方法中。像这样的：

class Person
{
  public void AddOrganization(Organization org, string details)
  {
    var link = new PeopleOrganization { ... };

    LinkToOrganization.Add(link)
    org.LinkToPeople.Add(link);
  }
}

这样您就不必自己创建内部实体了。