“/”应用程序中的服务器错误。

值不能为 null。
参数名: source

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.ArgumentNullException: 值不能为 null。
参数名: source

源错误:


行 30:     if (parameter.toId > 0)
行 31:     {
行 32:         var city = hotCity.FirstOrDefault(c => c.Item1 == parameter.toId);
行 33:         if (city != null) { toCity = city.Item3; }
行 34:         if (string.IsNullOrEmpty(toCity))

源文件: d:\alltrip\alltrip\Views\Line\LineList.cshtml    行: 32

堆栈跟踪:


[ArgumentNullException: 值不能为 null。
参数名: source]
   System.Linq.Enumerable.FirstOrDefault(IEnumerable`1 source, Func`2 predicate) +297
   ASP._Page_Views_Line_LineList_cshtml.Execute() in d:\alltrip\alltrip\Views\Line\LineList.cshtml:32
   System.Web.WebPages.WebPageBase.ExecutePageHierarchy() +252
   System.Web.Mvc.WebViewPage.ExecutePageHierarchy() +148
   System.Web.WebPages.StartPage.ExecutePageHierarchy() +86
   System.Web.WebPages.WebPageBase.ExecutePageHierarchy(WebPageContext pageContext, TextWriter writer, WebPageRenderingBase startPage) +107
   System.Web.Mvc.ViewResultBase.ExecuteResult(ControllerContext context) +375
   System.Web.Mvc.ControllerActionInvoker.InvokeActionResultFilterRecursive(IList`1 filters, Int32 filterIndex, ResultExecutingContext preContext, ControllerContext controllerContext, ActionResult actionResult) +88
   System.Web.Mvc.ControllerActionInvoker.InvokeActionResultFilterRecursive(IList`1 filters, Int32 filterIndex, ResultExecutingContext preContext, ControllerContext controllerContext, ActionResult actionResult) +775
   System.Web.Mvc.ControllerActionInvoker.InvokeActionResultWithFilters(ControllerContext controllerContext, IList`1 filters, ActionResult actionResult) +81
   System.Web.Mvc.Async.<>c__DisplayClass3_1.<BeginInvokeAction>b__1(IAsyncResult asyncResult) +188
   System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeAction(IAsyncResult asyncResult) +38
   System.Web.Mvc.<>c.<BeginExecuteCore>b__152_1(IAsyncResult asyncResult, ExecuteCoreState innerState) +26
   System.Web.Mvc.Async.WrappedAsyncVoid`1.CallEndDelegate(IAsyncResult asyncResult) +68
   System.Web.Mvc.Controller.EndExecuteCore(IAsyncResult asyncResult) +52
   System.Web.Mvc.Async.WrappedAsyncVoid`1.CallEndDelegate(IAsyncResult asyncResult) +39
   System.Web.Mvc.Controller.EndExecute(IAsyncResult asyncResult) +38
   System.Web.Mvc.<>c.<BeginProcessRequest>b__20_1(IAsyncResult asyncResult, ProcessRequestState innerState) +40
   System.Web.Mvc.Async.WrappedAsyncVoid`1.CallEndDelegate(IAsyncResult asyncResult) +68
   System.Web.Mvc.MvcHandler.EndProcessRequest(IAsyncResult asyncResult) +38
   System.Web.CallHandlerExecutionStep.InvokeEndHandler(IAsyncResult ar) +212
   System.Web.CallHandlerExecutionStep.OnAsyncHandlerCompletion(IAsyncResult ar) +166


版本信息: Microsoft .NET Framework 版本:4.0.30319; ASP.NET 版本:4.7.3930.0