如何使用流畅的nhibernate自动映射在同一个表中引用父实体?

时间:2015-07-21 08:30:44

标签: c# nhibernate fluent-nhibernate fluent-nhibernate-mapping

我正在尝试使用FluentNHibernate AutoMappings来创建一个引用其父级的实体。我能够在ClassMap<>的帮助下完成这项工作,但现在我想将所有内容移至AutoMappings。我有一个包含以下架构的表:

CREATE TABLE [dbo].[Job]
(
   [Id] INT NOT NULL IDENTITY(1,1), 
   [ParentId] INT NULL, 
   PRIMARY KEY ([Id]), 
   CONSTRAINT [FK_Job_Parent] FOREIGN KEY ([ParentId]) REFERENCES [Job]([Id]) 
)

以下C#代码:

using FluentNHibernate;
using FluentNHibernate.Automapping;
using FluentNHibernate.Cfg;
using FluentNHibernate.Cfg.Db;
using FluentNHibernate.Conventions;
using FluentNHibernate.Conventions.Instances;
using System;
using System.Configuration;

namespace NHibernateTest
{
    public class Program
    {
        private static void Main(string[] args)
        {
            var sessionFactory = Fluently.Configure()
              .Database(MsSqlConfiguration.MsSql2008.ConnectionString(ConfigurationManager.ConnectionStrings["Default"].ConnectionString))
              .Mappings(m =>
              {
                  m.AutoMappings.Add(
                      AutoMap.AssemblyOf<Program>(new MappingConfig()).Conventions.Setup(conv =>
                  {
                      conv.Add<DefaultReferenceConvention>();
                      conv.Add<DefaultHasManyConvention>();
                      conv.Add<SimpleForeignKeyConvention>();
                  }));
              })
              .BuildSessionFactory();

            using (var session = sessionFactory.OpenSession())
            {
                using (var tran = session.BeginTransaction())
                {
                   var jobs = session
                        .QueryOver<Job>()
                        .List<Job>();

                    tran.Commit();
                }
            }
        }
    }

    public class Job
    {
        public virtual int Id { get; set; }

        public virtual Job Parent { get; set; }
    }

    public class MappingConfig : DefaultAutomappingConfiguration
    {
        public override bool ShouldMap(Type type)
        {
            return type == typeof(Job);
        }
    }

    public class SimpleForeignKeyConvention : ForeignKeyConvention
    {
        protected override string GetKeyName(Member property, Type type)
        {
            if (property == null)
            {
                return type.Name + "Id";
            }

           return property.Name + "Id";
        }
    }

    public class DefaultHasManyConvention : IHasManyConvention
    {
        public void Apply(IOneToManyCollectionInstance instance)
        {
            instance.Key.Column(string.Format("{0}{1}", instance.EntityType.Name, "Id"));
            instance.LazyLoad();
        }
    }

    public class DefaultReferenceConvention : IReferenceConvention
    {
        public void Apply(IManyToOneInstance instance)
        {
            var col = string.Format("{0}Id", instance.Class.Name);
            instance.Column(col);
            instance.LazyLoad();
        }
    }
}

我得到了:

  

创建SessionFactory时使用了无效或不完整的配置。检查PotentialReasons集合,以及InnerException以获取更多详细信息。

     

外键(FK7D5D63A6AE42E0BA:作业[JobId,ParentId]))必须与引用的主键具有相同的列数(作业[Id])

有没有办法只使用自动映射来执行此操作?

0 个答案:

没有答案