“/”应用程序中的服务器错误。

序列不包含任何匹配元素

说明: 执行当前 Web 请求期间,出现未经处理的异常。请检查堆栈跟踪信息,以了解有关该错误以及代码中导致错误的出处的详细信息。

异常详细信息: System.InvalidOperationException: 序列不包含任何匹配元素

源错误:

执行当前 Web 请求期间生成了未经处理的异常。可以使用下面的异常堆栈跟踪信息确定有关异常原因和发生位置的信息。

堆栈跟踪:


[InvalidOperationException: 序列不包含任何匹配元素]
   System.Linq.Enumerable.First(IEnumerable`1 source, Func`2 predicate) +396
   Mammothcode.DeMa.web.Controllers.HomeController.ProblemFeedback(String roleId, Nullable`1 index) in F:\Gitlab\dema\src\Mammothcode.DeMa.Enweb\Controllers\HomeController.cs:76
   lambda_method(Closure , ControllerBase , Object[] ) +199
   System.Web.Mvc.ReflectedActionDescriptor.Execute(ControllerContext controllerContext, IDictionary`2 parameters) +280
   System.Web.Mvc.ControllerActionInvoker.InvokeActionMethod(ControllerContext controllerContext, ActionDescriptor actionDescriptor, IDictionary`2 parameters) +35
   System.Web.Mvc.Async.<>c__DisplayClass42.<BeginInvokeSynchronousActionMethod>b__41() +33
   System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeActionMethod(IAsyncResult asyncResult) +42
   System.Web.Mvc.Async.<>c__DisplayClass39.<BeginInvokeActionMethodWithFilters>b__33() +80
   System.Web.Mvc.Async.<>c__DisplayClass4f.<InvokeActionMethodFilterAsynchronously>b__49() +396
   System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeActionMethodWithFilters(IAsyncResult asyncResult) +42
   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) +38
   System.Web.Mvc.<>c__DisplayClass1d.<BeginExecuteCore>b__18(IAsyncResult asyncResult) +30
   System.Web.Mvc.Async.<>c__DisplayClass4.<MakeVoidDelegate>b__3(IAsyncResult ar) +25
   System.Web.Mvc.Controller.EndExecuteCore(IAsyncResult asyncResult) +52
   System.Web.Mvc.Async.<>c__DisplayClass4.<MakeVoidDelegate>b__3(IAsyncResult ar) +25
   System.Web.Mvc.Controller.EndExecute(IAsyncResult asyncResult) +38
   System.Web.Mvc.<>c__DisplayClass8.<BeginProcessRequest>b__3(IAsyncResult asyncResult) +44
   System.Web.Mvc.Async.<>c__DisplayClass4.<MakeVoidDelegate>b__3(IAsyncResult ar) +25
   System.Web.Mvc.MvcHandler.EndProcessRequest(IAsyncResult asyncResult) +38
   System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +431
   System.Web.HttpApplication.ExecuteStepImpl(IExecutionStep step) +75
   System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +158


版本信息: Microsoft .NET Framework 版本:4.0.30319; ASP.NET 版本:4.8.4110.0