Solved - Querying an entity with a condition on an associated entity's property

Question

I'm in a early phase of learning NHibernate, and currently I'm trying to select every person within a company or function. The code is listed below. I have some problems with conditions on the Person's associated properties. The person has one-to-many relation to Department, and I want to check the DepartmentName property of the related department. This is the same for Function, but I guess I'll manage that when I've understood the problems with Department. What am I doing wrong? :)

---

        using (var session = NHibernateHelper.OpenSession())
        {
            var criteria = session.CreateCriteria(typeof(Person));

            if (!string.IsNullOrEmpty(employeeNumber))
            {
                int emplNum; 
                int.TryParse(employeeNumber, out emplNum);
                criteria.Add(Restrictions.Eq("EmployeeNumber", emplNum));
            }

            if (!string.IsNullOrEmpty(name))
            {
                foreach (var token in name.Split(' '))
                {
                    var expr = string.Format("%{0}%", name);
                    criteria.Add(Restrictions.Or(
                        Restrictions.Like("FirstName", expr),
                        Restrictions.Like("LastName", expr)
                    ));
                }                    
            }

            if (!string.IsNullOrEmpty(department))
            {
                var expr = string.Format("%{0}%", department);
                criteria.SetFetchMode("Department", NHibernate.FetchMode.Eager);
                criteria.Add(Restrictions.Like("Department.DepartmentName", expr));
            }

            if (!string.IsNullOrEmpty(function))
            {
                var expr = string.Format("%{0}%", function);
                criteria.SetFetchMode("Function", NHibernate.FetchMode.Eager);
                criteria.Add(Restrictions.Like("Function.FunctionName", expr));
            }

            return criteria.List<Person>();

Update

I managed to do it by myself. I changed the department part to this:

if (!string.IsNullOrEmpty(department))
{
     var expr = string.Format("%{0}%", department);
     criteria.CreateAlias("Department", "dep")
         .SetFetchMode("Department", FetchMode.Eager)
         .Add(Restrictions.Like("dep.DepartmentName", expr));
}

Still, this might not be the preferred way, so leave a comment if I'm doing something horribly wrong :-)