Hi all,
I want to integrate NHibernate Mapping object with asp.net MemberShip User object. Here is my case:
Project class has 2 properties: Creator and Participant which is User class.
Project class is mapping by NHibernate, but User is created by MemberShip function. I know User object is not persistent.
When i create a Project object with Creator and Participant, which are the same User. I encounter a error "a different object with the same identifier value was already associated with the session".
I use a class ProjectDB to Add New Project:
public class ProjectDB : BaseDB<Project, Guid>, IProjectDB
{
public Project AddProject(Project project)
{
project = this.Save(project);
this.CommitChanges();
return project;
}
}
Do you have any idea to solve this problem.
Any help much appreciated.

sounds like you do something like:

User Creator = new User();
User.Id = 1;
//Fill in User Data here

User Participant = new User();
User.Id = 1;
//Fill in User Data here

Project p = new Project();
p.Creator = Creator;
p.Participant = Participant;
//Fill in Project Data here

I think that can't work because you've got two different objects with the same key in one Session.
You can overwrite the Equals() function. Now NHibernate should know that both Users are the same (Object.Equals() is only true if it is the same Object).

Maybe like this:

class User
{
...
public override Equals(object o)
{
if(o.GetType() != typeof(User))
return false;

User other = (User)o;
if( other.Id == this.Id )
return true;
else
return false;
}

Have a look here for more info about object identity with hibernate:

http://nhforge.org/blogs/nhibernate/archive/2008/09/06/identity-field-equality-and-hash-code.aspx

Thank you Reflection and Wolli. I have try implement User for Equals, = operator, and GetHashCode but i get the same error.
Are you sure that resolve my problem?
My best.

well if you're users are not persisted something like:



won't work anyway. How should NHibernate know what to do with those objects.
Maybe you could do something like:



Where the properties of your Project aren't MembershipUsers but plain Strings containing the Username.

Maybe the mapping files and the class definitions of your Project would help.

Greetings,
Reflection

It work, Reflection.
Here my Project define:
<?xml version="1.0" encoding="utf-8" ?>
<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2">
<class name="smartSTATUS.DTO.Project, smartSTATUS.DTO" table="smartSTATUS_Projects" lazy="false">
<id name="ProjectId" column="ProjectId" type="Guid">
<generator class="guid" />
</id>
<many-to-one cascade="none" name="Creator" class="smartSTATUS.DTO.User, smartSTATUS.DTO" column="CreatorId" foreign-key="UserId" />
<property name="Name" type="string"/>
<property name="Description" type="string"/>
<property name="Status" type="smartSTATUS.DTO.ProjectStatus, smartSTATUS.DTO" />
<property name="CreationDate" type="DateTime"/>
<bag name="Clients" table="smartSTATUS_ClientsInProjects" cascade="all">
<key column="ProjectId" />
<many-to-many column="ClientId" foreign-key="UserId" class="smartSTATUS.DTO.User, smartSTATUS.DTO" />
</bag>
<bag name="Participants" table="smartSTATUS_ParticipantsInProjects" cascade="all">
<key column="ProjectId" />
<many-to-many column="ParticipantId" foreign-key="UserId" class="smartSTATUS.DTO.User, smartSTATUS.DTO" />
</bag>
</class>
</hibernate-mapping>

I have resolved my problem.
The fault is i don't close old session and re-use that session for saving project.
NHibernate doesn't allow to save Project with Creator and Participant, which have the same identifier, in this case. I don't know why. If anyone can explain me, much appreciated.
However, i want to tell many thanks with you, who help me with nice enthusiasm.
My very best.