FluentNHibernate：使用属性和约定自动映射 OneToMany 关系

Question

这与我之前的问题非常相似： FluentNHibernate: How to Translation HasMany( x => x.Addresses).KeyColumn("PersonId") 进入自动映射

---

假设我有这些模型：

public class Person
{
    public virtual int Id { get; private set; }
    public virtual ICollection<Address> Addresses { get; private set; }
}

public class Address
{
    public virtual int Id { get; private set; }
    public virtual Person Owner { get; set; }
}

我想要FluentNHibernate 创建下表：

Person
    PersonId
Address
    AddressId
    OwnerId

这可以通过使用流畅映射轻松实现：

public class PersonMapping : ClassMap<Person>
{
    public PersonMapping()
    {
        Id(x => x.Id).Column("PersonId");
        HasMany(x => x.Addresses).KeyColumn("OwnerId");
    }
}

public class AddressMapping : ClassMap<Address>
{
    public AddressMapping()
    {
        Id(x => x.Id).Column("AddressId");
        References(x => x.Person).Column("OwnerId");
    }
}

我想通过使用自动映射获得相同的结果。我尝试了以下约定：

class PrimaryKeyNameConvention : IIdConvention
{
    public void Apply(IIdentityInstance instance)
    {
        instance.Column(instance.EntityType.Name + "Id");
    }
}

class ReferenceNameConvention : IReferenceConvention
{
    public void Apply(IManyToOneInstance instance)
    {
        instance.Column(string.Format("{0}Id", instance.Name));
    }
}

// Copied from @Fourth: https://stackoverflow.com/questions/6091290/fluentnhibernate-how-to-translate-hasmanyx-x-addresses-keycolumnpersonid/6091307#6091307
public class SimpleForeignKeyConvention : ForeignKeyConvention
{
    protected override string GetKeyName(Member property, Type type)
    {
        if(property == null)
            return type.Name + "Id";
        return property.Name + "Id";
    }
}

但它创建了下表：

Person
    PersonId
Address
    AddressId
    OwnerId
    PersonId // this column should not exist

所以我添加了 AutoMappingOverride：

public class PersonMappingOverride : IAutoMappingOverride<Person>
{
    public void Override(AutoMapping<Person> mapping)
    {
        mapping.HasMany(x => x.Addresses).KeyColumn("OwnerId");
    }
}

这正确解决了问题。但我想使用 attribute & 获得相同的结果习俗。我尝试过：

public class Person
{
    public virtual int Id { get; private set; }

    [KeyColumn("OwnerId")]
    public virtual ICollection<Address> Addresses { get; private set; }
}

class KeyColumnAttribute : Attribute
{
    public readonly string Name;

    public KeyColumnAttribute(string name)
    {
        Name = name;
    }
}

class KeyColumnConvention: IHasManyConvention
{
    public void Apply(IOneToManyCollectionInstance instance)
    {
        var keyColumnAttribute = (KeyColumnAttribute)Attribute.GetCustomAttribute(instance.Member, typeof(KeyColumnAttribute));
        if (keyColumnAttribute != null)
        {
            instance.Key.Column(keyColumnAttribute.Name);
        }
    }
}

但它创建了这些表：

Person
    PersonId
Address
    AddressId
    OwnerId
    PersonId // this column should not exist

下面是我的代码的其余部分：

ISessionFactory sessionFactory = Fluently.Configure()
    .Database(MsSqlConfiguration.MsSql2008.ConnectionString(connectionString))
    .Mappings(m =>
                m.AutoMappings.Add(AutoMap.Assemblies(typeof(Person).Assembly)
                    .Conventions.Add(typeof(PrimaryKeyNameConvention))
                          .Conventions.Add(typeof(PrimaryKeyNameConvention))
                          .Conventions.Add(typeof(ReferenceNameConvention))
                          .Conventions.Add(typeof(SimpleForeignKeyConvention))
                          .Conventions.Add(typeof(KeyColumnConvention)))

                //m.FluentMappings
                //    .Add(typeof (PersonMapping))
                //    .Add(typeof (AddressMapping))
    )
    .ExposeConfiguration(BuildSchema)
    .BuildConfiguration()
    .BuildSessionFactory();

有什么想法吗？谢谢。

---

更新：

测试项目可以从

Answer 1

唉……学习NHibernate真是一件揪心的经历。

不管怎样，我想我终于找到了解决这个问题的方法：只需删除 SimpleForeignKeyConvention ，一切都会正常工作。

似乎 SimpleForeignKeyConvention 与 ReferenceKeyConvention 和 ReferenceKeyConvention 都冲突。 KeyColumnConvention。它的优先级高于KeyColumnConvention，但低于ReferenceKeyConvention。

public class SimpleForeignKeyConvention : ForeignKeyConvention
{
    protected override string GetKeyName(Member property, Type type)
    {
        if(property == null)
            // This line will disable `KeyColumnConvention`
            return type.Name + "Id";

        // This line has no effect when `ReferenceKeyConvention` is enabled.
        return property.Name + "Id";
    }
}

Answer 2

我已经使用 FHN 的自动映射功能测试了您的类，它不会在地址表上创建第二个 PersonId。
我使用的是 此处 的 FHN v1.2.0.721