无法理解为什么我在加载页面时在ASP MVC中收到此nullReference异常

Question

我有一个Web应用程序,在我的计算机上没有给我任何问题,但当我将它部署到服务器时,我得到了这个错误.它没有给我任何源代码行检查,我不知道为什么它可能发生

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

Source Error: 


[No relevant source lines]

Source File: c:\Windows\Microsoft.NET\Framework64\v4.0.30319\Temporary ASP.NET Files\root\a9dc635c\ccb3814\App_Web_item.cshtml.f0356b3c.uyw8roer.0.cs    Line: 0 

Stack Trace: 


[NullReferenceException: Object reference not set to an instance of an object.]
   ASP._Page__AssemblyResource_MyProject_Web_Mvc__Version_1_0_0_0__Culture_neutral__PublicKeyToken_null_Views_LeagueGlobal_Item_cshtml.Execute() in c:\Windows\Microsoft.NET\Framework64\v4.0.30319\Temporary ASP.NET Files\root\a9dc635c\ccb3814\App_Web_item.cshtml.f0356b3c.uyw8roer.0.cs:0
   System.Web.WebPages.WebPageBase.ExecutePageHierarchy() +279
   System.Web.Mvc.WebViewPage.ExecutePageHierarchy() +125
   System.Web.WebPages.WebPageBase.ExecutePageHierarchy(WebPageContext pageContext, TextWriter writer, WebPageRenderingBase startPage) +195
   System.Web.Mvc.ViewResultBase.ExecuteResult(ControllerContext context) +383
   System.Web.Mvc.<>c__DisplayClass1a.<InvokeActionResultWithFilters>b__17() +32
   System.Web.Mvc.ControllerActionInvoker.InvokeActionResultFilter(IResultFilter filter, ResultExecutingContext preContext, Func`1 continuation) +977396
   System.Web.Mvc.ControllerActionInvoker.InvokeActionResultFilter(IResultFilter filter, ResultExecutingContext preContext, Func`1 continuation) +977396
   System.Web.Mvc.ControllerActionInvoker.InvokeActionResultWithFilters(ControllerContext controllerContext, IList`1 filters, ActionResult actionResult) +265
   System.Web.Mvc.Async.<>c__DisplayClass25.<BeginInvokeAction>b__22(IAsyncResult asyncResult) +964636
   System.Web.Mvc.<>c__DisplayClass1d.<BeginExecuteCore>b__18(IAsyncResult asyncResult) +28
   System.Web.Mvc.Async.<>c__DisplayClass4.<MakeVoidDelegate>b__3(IAsyncResult ar) +20
   System.Web.Mvc.Controller.EndExecuteCore(IAsyncResult asyncResult) +67
   System.Web.Mvc.Async.<>c__DisplayClass4.<MakeVoidDelegate>b__3(IAsyncResult ar) +20
   System.Web.Mvc.Controller.EndExecute(IAsyncResult asyncResult) +53
   System.Web.Mvc.<>c__DisplayClass8.<BeginProcessRequest>b__3(IAsyncResult asyncResult) +42
   System.Web.Mvc.Async.<>c__DisplayClass4.<MakeVoidDelegate>b__3(IAsyncResult ar) +20
   System.Web.Mvc.MvcHandler.EndProcessRequest(IAsyncResult asyncResult) +53
   System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +469
   System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +375

Answer 1

转到源文件的第 0 行：

c:\Windows\Microsoft.NET\Framework64\v4.0.30319\Temporary ASP.NET Files\root\a9dc635c\ccb3814\App_Web_item.cshtml.f0356b3c.uyw8roer.0.cs

然后，使用它来确定代码块中异常发生的确切位置：

try
{
   ...
}
catch (NullReferenceException ex)
{
      ShowMessageBox("Error" + ex.Message);
}

检查：

1. 您已经启动了正在操作的变量。
2. 自从将其部署到服务器以来，您正在使用的变量尚未变为空。
3. 您没有使用超出您范围的变量。