Server Error in '/' Application.

Sequence contains no elements

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.InvalidOperationException: Sequence contains no elements

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:


[InvalidOperationException: Sequence contains no elements]
   System.Linq.Enumerable.Single(IEnumerable`1 source) +311
   System.Data.Entity.Core.Objects.ELinq.ObjectQueryProvider.<GetElementFunction>b__3(IEnumerable`1 sequence) +40
   System.Data.Entity.Core.Objects.ELinq.ObjectQueryProvider.ExecuteSingle(IEnumerable`1 query, Expression queryRoot) +60
   System.Data.Entity.Core.Objects.ELinq.ObjectQueryProvider.System.Linq.IQueryProvider.Execute(Expression expression) +113
   System.Data.Entity.Internal.Linq.DbQueryProvider.Execute(Expression expression) +113
   System.Linq.Queryable.Single(IQueryable`1 source) +211
   CicekFilosu.Models.CITYHelper.SelectChampaignProductWithCity(String CityUrlName) in C:\Users\bitech\source\repos\LaleCicek\Solution\CicekFilosu\Models\CITYHelper.cs:15
   CicekFilosu.Controllers.CityController.Index() in C:\Users\bitech\source\repos\LaleCicek\Solution\CicekFilosu\Controllers\CityController.cs:44
   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) +182
   System.Web.Mvc.ControllerActionInvoker.InvokeActionMethod(ControllerContext controllerContext, ActionDescriptor actionDescriptor, IDictionary`2 parameters) +27
   System.Web.Mvc.Async.<>c__DisplayClass42.<BeginInvokeSynchronousActionMethod>b__41() +28
   System.Web.Mvc.Async.<>c__DisplayClass8`1.<BeginSynchronous>b__7(IAsyncResult _) +10
   System.Web.Mvc.Async.WrappedAsyncResult`1.End() +50
   System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeActionMethod(IAsyncResult asyncResult) +49
   System.Web.Mvc.Async.<>c__DisplayClass39.<BeginInvokeActionMethodWithFilters>b__33() +58
   System.Web.Mvc.Async.<>c__DisplayClass4f.<InvokeActionMethodFilterAsynchronously>b__49() +228
   System.Web.Mvc.Async.<>c__DisplayClass37.<BeginInvokeActionMethodWithFilters>b__36(IAsyncResult asyncResult) +10
   System.Web.Mvc.Async.WrappedAsyncResult`1.End() +50
   System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeActionMethodWithFilters(IAsyncResult asyncResult) +49
   System.Web.Mvc.Async.<>c__DisplayClass2a.<BeginInvokeAction>b__20() +24
   System.Web.Mvc.Async.<>c__DisplayClass25.<BeginInvokeAction>b__22(IAsyncResult asyncResult) +99
   System.Web.Mvc.Async.WrappedAsyncResult`1.End() +50
   System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeAction(IAsyncResult asyncResult) +44
   System.Web.Mvc.<>c__DisplayClass1d.<BeginExecuteCore>b__18(IAsyncResult asyncResult) +14
   System.Web.Mvc.Async.<>c__DisplayClass4.<MakeVoidDelegate>b__3(IAsyncResult ar) +16
   System.Web.Mvc.Async.WrappedAsyncResult`1.End() +50
   System.Web.Mvc.Controller.EndExecuteCore(IAsyncResult asyncResult) +55
   System.Web.Mvc.Async.<>c__DisplayClass4.<MakeVoidDelegate>b__3(IAsyncResult ar) +16
   System.Web.Mvc.Async.WrappedAsyncResult`1.End() +50
   System.Web.Mvc.Controller.EndExecute(IAsyncResult asyncResult) +45
   System.Web.Mvc.Controller.System.Web.Mvc.Async.IAsyncController.EndExecute(IAsyncResult asyncResult) +10
   System.Web.Mvc.<>c__DisplayClass8.<BeginProcessRequest>b__3(IAsyncResult asyncResult) +25
   System.Web.Mvc.Async.<>c__DisplayClass4.<MakeVoidDelegate>b__3(IAsyncResult ar) +16
   System.Web.Mvc.Async.WrappedAsyncResult`1.End() +50
   System.Web.Mvc.MvcHandler.EndProcessRequest(IAsyncResult asyncResult) +45
   System.Web.Mvc.MvcHandler.System.Web.IHttpAsyncHandler.EndProcessRequest(IAsyncResult result) +9
   System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +9875181
   System.Web.HttpApplication.ExecuteStepImpl(IExecutionStep step) +48
   System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +159


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