I am using NHibernate 1.2 under Visual Studio 2008 (VS2008) Web Application which dumps all the App_Code files into App_Code assembly, i.e., there's no right click to embed file.

In my User.hbm.xml I've tried various permutations of setting namespace, assembly and classname teg values to various resolutions off App_Code.NHbernateHelpers.User. I've tried stepping through the source code and have yet to determine where/what causes the exception Unknown entity class: NHibernateHelpers.User

I have also tried the constructor
static NHibernateHelper()
{
Configuration cfg = new Configuration().Configure();
cfg.AddDirectory(new System.IO.DirectoryInfo(HttpContext.Current.Server.MapPath(@"~/App_Code/")));
sessionFactory = cfg.BuildSessionFactory();
}


The exception is throw at the session.Save(u); line here...
protected void Page_Load(object sender, EventArgs e)
{
ISession session = NHibernateHelper.GetCurrentSession();
ITransaction tx = session.BeginTransaction();
User u = new User();
u.Name = "Joe";
session.Save(u);
tx.Commit();
NHibernateHelper.CloseSession();
}

It seems as if the App_Code qualifier gets lost in the sauce. So much for a quick start.

Have you set the build action of your mapping file (hbm.xml) to embedded resource ?

I've also had this probelm and I only found two solutions:

1. Use a old style Website-Project in VS. That will give you the possibility to name the assembly.
2. Create a library for your business objects and mappings.

I've chosen solution 2 because of the drawbacks old Website-Projects have.

In a Web Project's App_Code there is no right-click "Properties" menu pick that yields a property sheet with a "Build Action" selector the way there is in a class library project. See next post.

Thanks! This was road to success. It also matched the paradigm I typically use for solution organization. A Web UI, classLibrary BO (Business Objects/Logic) project and another classLibrary DA (Data Access) project. I tried a couple of ways to organize and found that you can put the hbm mapping files by themselves in the DA project and point at them from web.cofig setting. For the hbm content itself you need to set the assembly and namespace attributes to point to the BO project assembly and all works well.

NOTE -- as whoami suggests, one does need to set the Build Action to Embedded Resource; to do so, with the *.hbm.xml file in a class library project, right-click on the file, select Properties and in the Advanced Section find the Build Action property listed with its drop-down selector.

Tested okay with NHibernate 2.0.0-GA too.





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