I am trying to map a Member to a Member Address as a one-to-one mapping. The Member table contains the field AddressID which stores the value of the Primary key of the Members address from the Address table. A member dosent have to have an address. I have tried using the examples to find a solution but I keep getting the error "An association from the table Members refers to an unmapped class: Address" This is my member and address mapping

<?xml version="1.0" encoding="utf-8" ?>
<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2">
<class name="Test.Core.Domain.Member, Test.Core" table="Members" lazy="false">
<id name="MemberID" column="MemberID" type="Int32" unsaved-value="0">
<generator class="native" />
</id>
<property name="UserName" column="UserName" type="String" />
<one-to-one name="Address" class="Test.Core.Domain.Address, Test.Core" />
</class>
</hibernate-mapping>

<?xml version="1.0" encoding="utf-8" ?>
<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2">
<class name="Test.Core.Domain.Address, Test.Core" table="Address" lazy="false">
<id name="AddressID" column="AddressID" type="Int32" unsaved-value="0">
<generator class="native" />
</id>
<property name="HouseNumber" column="HouseNumber" type="Int32" />
<property name="Street" column="Street" type="String" />
<property name="City" column="City" type="String" />
<property name="County" column="County" type="String" />
<property name="State" column="State" type="String" />
<property name="Postcode" column="Postcode" type="String" />
<property name="Country" column="Country" type="String" />
</class>
</hibernate-mapping>

Can anyone help me to get this working? Do I need to update the Address mapping file also?
Thanks in advance

This message sounds more like hibernate doesn't know this class. Can you read/write Address entities ?



Afaik that's not possible with a one-to-one. Try a many-to-one instead with unique="true":

Ok, I have tried simply reading from the address table with the following error:

NHibernate.MappingException: Unknown entity class: Test.Core.Domain.Address

I realise my problem is that hibernate does not know about my Address class. I can't figure out why. I have created a simple Address class with a simple mapping file in the same way as my Member class and I have no problem to read the data from the Member table. Can you help me to figure this out please?

This is my method for displaying all Members:

private void DisplayAllMembers()
{
IDaoFactory daoFactory = new NHibernateDaoFactory();
IMemberDao memberDao = daoFactory.GetMemberDao();

grdMembers.DataSource = memberDao.GetAll();
grdMembers.DataBind();
}

and this one for displaying all Addresses:

private void DisplayAllAddresses()
{
IDaoFactory daoFactory = new NHibernateDaoFactory();
IAddressDao addressDao = daoFactory.GetAddressDao();

grdAddresses.DataSource = addressDao.GetAll();
}

IDAOFactory interface contains the following:

using Test.Core.Domain;

namespace Test.Core.DataInterfaces
{
public interface IDaoFactory
{
IAddressDao GetAddressDao();
IMemberDao GetMemberDao();
}

#region Inline interface declarations

public interface IMemberDao : IDao<Member> { }

public interface IAddressDao : IDao<Address> { }

#endregion
}

IDAO interface contains the following:

using System.Collections.Generic;

namespace Test.Core.DataInterfaces
{
public interface IDao<T>
{
List<T> GetAll();
}
}

NHibernateDaoFactory class contains the following:

using Test.Core.DataInterfaces;
using Test.Core.Domain;

namespace Test.Data
{
public class NHibernateDaoFactory : IDaoFactory
{
public IMemberDao GetMemberDao()
{
return new MemberDao();
}

public IAddressDao GetAddressDao()
{
return new AddressDao();
}

#region Inline DAO implementations

public class MemberDao : AbstractNHibernateDao<Member>, IMemberDao { }

public class AddressDao : AbstractNHibernateDao<Address>, IAddressDao { }

#endregion
}
}

AbstractNHibernateDao class contains the following:

using System;
using System.Collections.Generic;
using NHibernate;
using NHibernate.Expression;
using Test.Core.DataInterfaces;


namespace Test.Data
{
public abstract class AbstractNHibernateDao<T> : IDao<T>
{
public List<T> GetAll()
{
return GetByCriteria();
}

public List<T> GetByCriteria(params ICriterion[] criterion)
{
ICriteria criteria = NHibernateSession.CreateCriteria(persitentType);

foreach (ICriterion criterium in criterion)
{
criteria.Add(criterium);
}

return criteria.List<T>() as List<T>;
}

}
}

How do you add your mapping files ?

- in the configuration file >> is Address.hbm.xml added there
- via cfg.AddClass/AddAssembly >> is Address.hbm.xml marked as "EmbeddedRessource" in VS
- cfg.AddFile("Address.hbm.xml")

Check the debug log if the mapping file is read.

I got it, The mapping file was not in the Test.Core.csproj file as

<EmbeddedResource Include="Domain\Address.hbm.xml">
</EmbeddedResource>
I didn't have to add the Member.hbm.xml as it was there already. Why was the Member mapping there and not the Address?

Thanks for your help. I think I need to spend some more time getting this right before I move on.

When you add a new xml to your project, it defaults to "Content" I think. You have to change it manually. I forgot this so many times myself ...