static void

using System;
using System.Web;
using NHibernate;
using NHibernate.Context;
using Northwind;
 
/// <summary>
/// A simple HttpModule which loads NHibernate session
/// </summary>
public class NHibernateModule : IHttpModule
{
    #region Implementation of IHttpModule
 
    /// <summary>
    /// Initializes a module and prepares it to handle requests.
    /// </summary>
    /// <param name="context">An <see cref="T:System.Web.HttpApplication"/> that provides access to the methods, properties, and events common to all application objects within an ASP.NET application
    /// </param>
    public void Init(HttpApplication context)
    {
        context.BeginRequest += context_BeginRequest;
        context.EndRequest += context_EndRequest;
    }
 
    private static void context_BeginRequest(object sender, EventArgs e)
    {
        //use my session manager
        ISession session = SessionManager.Instance.OpenSession();
        CurrentSessionContext.Bind(session);
    }
 
    private static void context_EndRequest(object sender, EventArgs e)
    {
        ISessionFactory sessionFactory = SessionManager.Instance.SessionFactory;
        ISession session = CurrentSessionContext.Unbind(sessionFactory);
 
        if (session == null) return;
        if (session.Transaction != null)
        {
            if (session.Transaction.IsActive)
            {
                //if there is an active session, commit it
                session.Transaction.Commit();
            }
            else
            {
                //
                session.Transaction.Rollback();
            }
        }
 
        session.Close();
    }
 
    /// <summary>
    /// Disposes of the resources (other than memory) used by the module that implements <see cref="T:System.Web.IHttpModule"/>.
    /// </summary>
    public void Dispose()
    {
    }
 
    #endregion
}

<configuration>

   <!-- IIS 6 -->
    <system.web>
         <httpModules>
            <add name="NHibernateModule" type="NHibernateModule"/>
        </httpModules>
     </system.web>
     <!-- IIS 7 and Cassini. -->
    <system.webServer>
         <modules>
            <add name="NHibernateModule" type="NHibernateModule"/>
        </modules>
    </system.webServer>
</configuration>

<property name="current_session_context_class">
web
</property>