+1  A: 

The best solution is NOT to expose your persistent classes in the service.

Instead, create DTO classes that contain only the information needed by each service call, and expose those.

You can use AutoMapper to avoid part of the work of mapping from/to the DTOs and the persistent classes.

Diego Mijelshon  2010-04-15 00:19:25
Do you have any advice around changing the persistent class? IE, if i change the PersonName property to CustomerName.. it will break items inside the DTO. How should this be managed?
ChrisKolenko  2010-04-15 00:32:37
I'm still a little weight when it comes to NHibernate, but can you use some sort of ResultsTransformer to create the DTO? It seems silly to create IList<PersonDTO> by looping through a list of IList<Person>.. an example of using AutoMapper and NHibernate would be great to :D
ChrisKolenko  2010-04-15 00:48:44
I didn't understand the first question. For the second one, you could use the AliasToBeanResultTransformer and do the projections in HQL, but it's a little fragile. Another way is using Linq to Objects to project the exact DTO that you want from the original entities, either with AutoMapper or manually (sorry, I don't have samples, but it shouldn't be hard; check the included ones)
Diego Mijelshon  2010-04-15 11:09:19

related questions

IQuery NHibernate - does it HAVE to be a list?
(N)Hibernate - is it possible to dynamically map multiple tables to the one class
How can I map a list of strings to my entity using NHibernate?
Best practices for querying with NHibernate
NHibernate ISession Flush: Where and when to use it, and why?
IList.Cast<typeof(T)>() returns error, syntax looks ok
NHibernate Generators
101 tutorial for setting up nhibernate?
NHibernate Session.Flush() Sending Update Queries When No Update Has Occurred
NHibernate SetTimeout on ICriteria
Best way to manage session in NHibernate?
Has anyone moved to NHibernate 2.0 in a production environment?
NHIbernate: Difference between Restriction.In and Restriction.InG
NHibernate and Oracle connect through Windows Authenication
Is it possible to use nHibernate with Paradox database?
NHibernate 1.2 to 2.0 migration
NHibernate vs LINQ to SQL
Windows Service Increasing CPU Consumption
(N)Hibernate Auto-Join
MSTest and NHibernate
SQL 2008 Dialect Support for NHibernate
ADO.NET Entity vs NHibernate
Data Auditing in NHibernate and SqlServer
Best way to model Many-To-One Relationships in NHibernate When Dealing With a Legacy DB?
Subsonic Vs NHibernate