Nhibernate query throws NullReferenceException

Ismael123

Member
Joined
May 13, 2016
Messages
14
Programming Experience
1-3
Hi, I added a register form and a database driven authentication to a project I'm working on. Since then, I get a null reference error without seeing any validation summary when I try log in. The same thing happens when i try opening the register page. But errors occur when the app is reading something. I checked my web config and mapping but I couldnt find what causes the error. But I still think the error should at the mappings as I'm new to NHibernate. The whole source code can be found on: github.com/ismailousa/HastaneRandevu

C#:
[HttpPost]      
  public ActionResult Login(AuthLogin form, string returnUrl)
        {
            var user = Database.Session.Query<User>().FirstOrDefault(u => u.KimlikNo == form.KimlikNo);// I get the error here


            if (user == null)
                HastaneRandevu.Models.User.FakeHash();


            if (user == null || !user.CheckPassword(form.Password))
                ModelState.AddModelError("Kimlik No", "Kimlik No ya da Sifre yanlistir");
            if (!ModelState.IsValid)
            {
                return View(form);
            }
            FormsAuthentication.SetAuthCookie(user.KimlikNo, true);


            if (!string.IsNullOrWhiteSpace(returnUrl))
                return Redirect(returnUrl);


            if (User.IsInRole("Admin"))
                return Content("Welcome Admin");
            else if (User.IsInRole("Doktor"))
                return Content("Welcome Doc");
            else
                return RedirectToRoute("Home");
        }
C#:
public ActionResult New()
        {


            return View(new UsersNew()
            {
                Cinsiyetler = Database.Session.Query<Cinsiyet>().Select(  //and here when trying to load sex and role info
                    cinsiyet => new CinsiyetRadioBox()
                    {
                        Id = cinsiyet.Id,
                        Name = cinsiyet.Name
                    }).ToList(),
                Roles = Database.Session.Query<Role>().Select(
                    role => new RoleCheckBox()
                    {
                        Id = role.Id,
                        Name = role.Name
                    }).ToList()
            });
        }
 

Ismael123

Member
Joined
May 13, 2016
Messages
14
Programming Experience
1-3
C#:
[NullReferenceException: Object reference not set to an instance of an object.]
   NHibernate.Linq.LinqExtensionMethods.Query(ISession session) +44
   HastaneRandevu.Controllers.AuthController.Login(AuthLogin form, String returnUrl) in C:\Visual Studio 2017\Projects\HastaneRandevu\HastaneRandevu\Controllers\AuthController.cs:23
   lambda_method(Closure , ControllerBase , Object[] ) +147
   System.Web.Mvc.ActionMethodDispatcher.Execute(ControllerBase controller, Object[] parameters) +14
   System.Web.Mvc.ReflectedActionDescriptor.Execute(ControllerContext controllerContext, IDictionary`2 parameters) +157
   System.Web.Mvc.ControllerActionInvoker.InvokeActionMethod(ControllerContext controllerContext, ActionDescriptor actionDescriptor, IDictionary`2 parameters) +27
   System.Web.Mvc.Async.AsyncControllerActionInvoker.<BeginInvokeSynchronousActionMethod>b__39(IAsyncResult asyncResult, ActionInvocation innerInvokeState) +22
   System.Web.Mvc.Async.WrappedAsyncResult`2.CallEndDelegate(IAsyncResult asyncResult) +29
   System.Web.Mvc.Async.WrappedAsyncResultBase`1.End() +49
   System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeActionMethod(IAsyncResult asyncResult) +32
   System.Web.Mvc.Async.AsyncInvocationWithFilters.<InvokeActionMethodFilterAsynchronouslyRecursive>b__3d() +50
   System.Web.Mvc.Async.<>c__DisplayClass46.<InvokeActionMethodFilterAsynchronouslyRecursive>b__3f() +225
   System.Web.Mvc.Async.<>c__DisplayClass33.<BeginInvokeActionMethodWithFilters>b__32(IAsyncResult asyncResult) +10
   System.Web.Mvc.Async.WrappedAsyncResult`1.CallEndDelegate(IAsyncResult asyncResult) +10
   System.Web.Mvc.Async.WrappedAsyncResultBase`1.End() +49
   System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeActionMethodWithFilters(IAsyncResult asyncResult) +34
   System.Web.Mvc.Async.<>c__DisplayClass2b.<BeginInvokeAction>b__1c() +26
   System.Web.Mvc.Async.<>c__DisplayClass21.<BeginInvokeAction>b__1e(IAsyncResult asyncResult) +100
   System.Web.Mvc.Async.WrappedAsyncResult`1.CallEndDelegate(IAsyncResult asyncResult) +10
   System.Web.Mvc.Async.WrappedAsyncResultBase`1.End() +49
   System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeAction(IAsyncResult asyncResult) +27
   System.Web.Mvc.Controller.<BeginExecuteCore>b__1d(IAsyncResult asyncResult, ExecuteCoreState innerState) +13
   System.Web.Mvc.Async.WrappedAsyncVoid`1.CallEndDelegate(IAsyncResult asyncResult) +29
   System.Web.Mvc.Async.WrappedAsyncResultBase`1.End() +49
   System.Web.Mvc.Controller.EndExecuteCore(IAsyncResult asyncResult) +36
   System.Web.Mvc.Controller.<BeginExecute>b__15(IAsyncResult asyncResult, Controller controller) +12
   System.Web.Mvc.Async.WrappedAsyncVoid`1.CallEndDelegate(IAsyncResult asyncResult) +22
   System.Web.Mvc.Async.WrappedAsyncResultBase`1.End() +49
   System.Web.Mvc.Controller.EndExecute(IAsyncResult asyncResult) +26
   System.Web.Mvc.Controller.System.Web.Mvc.Async.IAsyncController.EndExecute(IAsyncResult asyncResult) +10
   System.Web.Mvc.MvcHandler.<BeginProcessRequest>b__5(IAsyncResult asyncResult, ProcessRequestState innerState) +21
   System.Web.Mvc.Async.WrappedAsyncVoid`1.CallEndDelegate(IAsyncResult asyncResult) +29
   System.Web.Mvc.Async.WrappedAsyncResultBase`1.End() +49
   System.Web.Mvc.MvcHandler.EndProcessRequest(IAsyncResult asyncResult) +28
   System.Web.Mvc.MvcHandler.System.Web.IHttpAsyncHandler.EndProcessRequest(IAsyncResult result) +9
   System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +9765045
   System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +155[CODE]
[CODE]
[NullReferenceException: Object reference not set to an instance of an object.]
   NHibernate.Linq.LinqExtensionMethods.Query(ISession session) +44
   HastaneRandevu.Controllers.UsersController.New() in C:\Visual Studio 2017\Projects\HastaneRandevu\HastaneRandevu\Controllers\UsersController.cs:18
   lambda_method(Closure , ControllerBase , Object[] ) +62
   System.Web.Mvc.ActionMethodDispatcher.Execute(ControllerBase controller, Object[] parameters) +14
   System.Web.Mvc.ReflectedActionDescriptor.Execute(ControllerContext controllerContext, IDictionary`2 parameters) +157
   System.Web.Mvc.ControllerActionInvoker.InvokeActionMethod(ControllerContext controllerContext, ActionDescriptor actionDescriptor, IDictionary`2 parameters) +27
   System.Web.Mvc.Async.AsyncControllerActionInvoker.<BeginInvokeSynchronousActionMethod>b__39(IAsyncResult asyncResult, ActionInvocation innerInvokeState) +22
   System.Web.Mvc.Async.WrappedAsyncResult`2.CallEndDelegate(IAsyncResult asyncResult) +29
   System.Web.Mvc.Async.WrappedAsyncResultBase`1.End() +49
   System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeActionMethod(IAsyncResult asyncResult) +32
   System.Web.Mvc.Async.AsyncInvocationWithFilters.<InvokeActionMethodFilterAsynchronouslyRecursive>b__3d() +50
   System.Web.Mvc.Async.<>c__DisplayClass46.<InvokeActionMethodFilterAsynchronouslyRecursive>b__3f() +225
   System.Web.Mvc.Async.<>c__DisplayClass33.<BeginInvokeActionMethodWithFilters>b__32(IAsyncResult asyncResult) +10
   System.Web.Mvc.Async.WrappedAsyncResult`1.CallEndDelegate(IAsyncResult asyncResult) +10
   System.Web.Mvc.Async.WrappedAsyncResultBase`1.End() +49
   System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeActionMethodWithFilters(IAsyncResult asyncResult) +34
   System.Web.Mvc.Async.<>c__DisplayClass2b.<BeginInvokeAction>b__1c() +26
   System.Web.Mvc.Async.<>c__DisplayClass21.<BeginInvokeAction>b__1e(IAsyncResult asyncResult) +100
   System.Web.Mvc.Async.WrappedAsyncResult`1.CallEndDelegate(IAsyncResult asyncResult) +10
   System.Web.Mvc.Async.WrappedAsyncResultBase`1.End() +49
   System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeAction(IAsyncResult asyncResult) +27
   System.Web.Mvc.Controller.<BeginExecuteCore>b__1d(IAsyncResult asyncResult, ExecuteCoreState innerState) +13
   System.Web.Mvc.Async.WrappedAsyncVoid`1.CallEndDelegate(IAsyncResult asyncResult) +29
   System.Web.Mvc.Async.WrappedAsyncResultBase`1.End() +49
   System.Web.Mvc.Controller.EndExecuteCore(IAsyncResult asyncResult) +36
   System.Web.Mvc.Controller.<BeginExecute>b__15(IAsyncResult asyncResult, Controller controller) +12
   System.Web.Mvc.Async.WrappedAsyncVoid`1.CallEndDelegate(IAsyncResult asyncResult) +22
   System.Web.Mvc.Async.WrappedAsyncResultBase`1.End() +49
   System.Web.Mvc.Controller.EndExecute(IAsyncResult asyncResult) +26
   System.Web.Mvc.Controller.System.Web.Mvc.Async.IAsyncController.EndExecute(IAsyncResult asyncResult) +10
   System.Web.Mvc.MvcHandler.<BeginProcessRequest>b__5(IAsyncResult asyncResult, ProcessRequestState innerState) +21
   System.Web.Mvc.Async.WrappedAsyncVoid`1.CallEndDelegate(IAsyncResult asyncResult) +29
   System.Web.Mvc.Async.WrappedAsyncResultBase`1.End() +49
   System.Web.Mvc.MvcHandler.EndProcessRequest(IAsyncResult asyncResult) +28
   System.Web.Mvc.MvcHandler.System.Web.IHttpAsyncHandler.EndProcessRequest(IAsyncResult result) +9
   System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +9765045
   System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +155[CODE]
 

jmcilhinney

C# Forum Moderator
Staff member
Joined
Apr 23, 2011
Messages
3,792
Location
Sydney, Australia
Programming Experience
10+
The first thing you should do is confirm that Database.Session is not null. If it's not then you should just call ToList on the result of Query and see whether it contains what you expect.
 

Ismael123

Member
Joined
May 13, 2016
Messages
14
Programming Experience
1-3
As you said, Database.Session returns null. I checked the connection strings but everything seems to be correct and I am mapping my models to their corresponding tables in the DB. I tried checking it again with a friend but we couldn't find the cause. What else can cause the session to return null?

<hibernate-configuration xmlns="urn:nhibernate-configuration-2.2">
<session-factory>
<property name="dialect">NHibernate.Dialect.MySQLDialect</property>
<property name="connection.driver_class">NHibernate.Driver.MySqlDataDriver</property>
<property name="connection.connection_string_name">MainDb</property>
</session-factory>
</hibernate-configuration>


<connectionStrings>
<add name="MainDb" connectionString="Server=localhost;Database=hastanerandevu;Uid=root;Pwd=;" />
</connectionStrings>
 

Ismael123

Member
Joined
May 13, 2016
Messages
14
Programming Experience
1-3
I found my mistake. Although I configure my database, I forgot to write the open and close session functions which are called for each query.
        public static void OpenSession()
        {
            HttpContext.Current.Items[SessionKey] = _sessionFactory.OpenSession();
        }


        public static void CloseSession()
        {
            var session = HttpContext.Current.Items[SessionKey] as ISession;
            if (session != null)
            {
                session.Close();
            }
            HttpContext.Current.Items.Remove(SessionKey);
        }
 
Top Bottom