Server Error in '/' Application.

Object reference not set to an instance of an object.

Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.NullReferenceException: Object reference not set to an instance of an object.

Source Error:

An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.

Stack Trace:


[NullReferenceException: Object reference not set to an instance of an object.]
   System.Data.Objects.ELinq.QueryParameterExpression.EvaluateParameter(Object[] arguments) +423
   System.Data.Objects.ELinq.ELinqQueryState.GetExecutionPlan(Nullable`1 forMergeOption) +1514
   System.Data.Objects.ObjectQuery`1.GetResults(Nullable`1 forMergeOption) +152
   System.Data.Objects.ObjectQuery`1.System.Collections.Generic.IEnumerable<T>.GetEnumerator() +40
   System.Linq.Enumerable.Single(IEnumerable`1 source) +142
   PagedList.PagedList`1..ctor(IQueryable`1 superset, Int32 pageNumber, Int32 pageSize) +93
   WebUnicity.Controllers.KhoaToController.GetArticle(Nullable`1 page, ArticleCategory cat) in H:\A_WORK\CDSP_GiaLai\cdspgialai\cdspgialaiv1.1\Controllers\KhoaToController.cs:56
   WebUnicity.Controllers.KhoaToController.Category(Int32 id, Nullable`1 page) in H:\A_WORK\CDSP_GiaLai\cdspgialai\cdspgialaiv1.1\Controllers\KhoaToController.cs:38
   lambda_method(Closure , ControllerBase , Object[] ) +205
   System.Web.Mvc.ReflectedActionDescriptor.Execute(ControllerContext controllerContext, IDictionary`2 parameters) +253
   System.Web.Mvc.ControllerActionInvoker.InvokeActionMethod(ControllerContext controllerContext, ActionDescriptor actionDescriptor, IDictionary`2 parameters) +35
   System.Web.Mvc.Async.<>c__DisplayClass42.<BeginInvokeSynchronousActionMethod>b__41() +34
   System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeActionMethod(IAsyncResult asyncResult) +57
   System.Web.Mvc.Async.<>c__DisplayClass39.<BeginInvokeActionMethodWithFilters>b__33() +77
   System.Web.Mvc.Async.<>c__DisplayClass4f.<InvokeActionMethodFilterAsynchronously>b__49() +372
   System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeActionMethodWithFilters(IAsyncResult asyncResult) +57
   System.Web.Mvc.Async.<>c__DisplayClass2a.<BeginInvokeAction>b__20() +32
   System.Web.Mvc.Async.<>c__DisplayClass25.<BeginInvokeAction>b__22(IAsyncResult asyncResult) +187
   System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeAction(IAsyncResult asyncResult) +50
   System.Web.Mvc.<>c__DisplayClass1d.<BeginExecuteCore>b__18(IAsyncResult asyncResult) +24
   System.Web.Mvc.Async.<>c__DisplayClass4.<MakeVoidDelegate>b__3(IAsyncResult ar) +25
   System.Web.Mvc.Controller.EndExecuteCore(IAsyncResult asyncResult) +64
   System.Web.Mvc.Async.<>c__DisplayClass4.<MakeVoidDelegate>b__3(IAsyncResult ar) +25
   System.Web.Mvc.Controller.EndExecute(IAsyncResult asyncResult) +50
   System.Web.Mvc.<>c__DisplayClass8.<BeginProcessRequest>b__3(IAsyncResult asyncResult) +38
   System.Web.Mvc.Async.<>c__DisplayClass4.<MakeVoidDelegate>b__3(IAsyncResult ar) +25
   System.Web.Mvc.MvcHandler.EndProcessRequest(IAsyncResult asyncResult) +50
   System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +602
   System.Web.HttpApplication.ExecuteStepImpl(IExecutionStep step) +195
   System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +128


Version Information: Microsoft .NET Framework Version:4.0.30319; ASP.NET Version:4.7.4087.0