System.Web.Routing.RouteCollection.GetRouteData中的异常

Question

我在iis7上运行的asp.net mvc代码中随机获得了两个异常:

Exception type: InvalidOperationException 
Exception message: Collection was modified; enumeration operation may not execute. 
   at System.ThrowHelper.ThrowInvalidOperationException(ExceptionResource resource)
   at System.Collections.Generic.List'1.Enumerator.MoveNextRare()
   at System.Collections.Generic.List'1.Enumerator.MoveNext()
   at System.Web.Routing.RouteCollection.GetRouteData(HttpContextBase httpContext)
   at System.Web.Routing.UrlRoutingModule.PostResolveRequestCache(HttpContextBase context)
   at System.Web.Routing.UrlRoutingModule.OnApplicationPostResolveRequestCache(Object sender, EventArgs e)
   at System.Web.HttpApplication.SyncEventExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute()
   at System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously)

和

Exception type: NullReferenceException 
Exception message: Object reference not set to an instance of an object. 
   at System.Web.Routing.RouteCollection.GetRouteData(HttpContextBase httpContext)
   at System.Web.Routing.UrlRoutingModule.PostResolveRequestCache(HttpContextBase context)
   at System.Web.Routing.UrlRoutingModule.OnApplicationPostResolveRequestCache(Object sender, EventArgs e)
   at System.Web.HttpApplication.SyncEventExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute()
   at System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously)

它不是一贯可重复的,但我认为它是改变(或腐败)的东西RouteTable.Routes.我RouteTable.Routes在项目中访问的唯一地方是Global.asax.cs,我知道那里的代码只被调用一次,所以这不是问题.有关如何追踪它的任何想法？

Answer 1

在我的例子中,它最终成为一个HttpModule:Ext.Direct.Mvc(ASP.NET MVC的Ext.Direct).该模块有一个错误(在0.8.0版本中已修复),每次为IHttpModule调用Init()时都会再次注册路由.(可能多次调用).如果时机合适,它将破坏RouteTable.Routes集合,并导致上述两个例外中的一个.