无法将“ASP._Page__ViewStart_cshtml”类型的对象转换为“System.Web.WebPages.StartPage”。错误

Question

我得到了 Unable to cast 类型的对象

ASP._Page__ViewStart_cshtml' 输入 'System.Web.WebPages.StartPage'

当我运行我的 MVC 应用程序时。

我在搜索时找到的每个答案都告诉我要确保我的 _ViewStart 文件在我的 Views 中> 文件夹，它就是。更奇怪的是，我将完全相同的项目文件从旧的 Win 7 PC 复制到了新的 Win 10 笔记本电脑上。该应用程序在旧 PC 上运行良好，但在新笔记本电脑上出现上述错误。我也在 Visual Studio 2015 中同时运行。

还有其他想法吗？

完整的错误信息：

[InvalidCastException: Unable to cast object of type 'ASP._Page__ViewStart_cshtml' to type 'System.Web.WebPages.StartPage'.]
   System.Web.WebPages.StartPage.GetStartPage(WebPageRenderingBase page, String fileName, IEnumerable`1 supportedExtensions) +236
   System.Web.Mvc.RazorView.RenderView(ViewContext viewContext, TextWriter writer, Object instance) +163
   System.Web.Mvc.BuildManagerCompiledView.Render(ViewContext viewContext, TextWriter writer) +107
   System.Web.Mvc.ViewResultBase.ExecuteResult(ControllerContext context) +291
   System.Web.Mvc.ControllerActionInvoker.InvokeActionResult(ControllerContext controllerContext, ActionResult actionResult) +13
   System.Web.Mvc.<>c__DisplayClass1c.<InvokeActionResultWithFilters>b__19() +23
   System.Web.Mvc.ControllerActionInvoker.InvokeActionResultFilter(IResultFilter filter, ResultExecutingContext preContext, Func`1 continuation) +245
   System.Web.Mvc.<>c__DisplayClass1e.<InvokeActionResultWithFilters>b__1b() +22
   System.Web.Mvc.ControllerActionInvoker.InvokeActionResultWithFilters(ControllerContext controllerContext, IList`1 filters, ActionResult actionResult) +176
   System.Web.Mvc.ControllerActionInvoker.InvokeAction(ControllerContext controllerContext, String actionName) +311
   System.Web.Mvc.Controller.ExecuteCore() +105
   System.Web.Mvc.ControllerBase.Execute(RequestContext requestContext) +88
   System.Web.Mvc.ControllerBase.System.Web.Mvc.IController.Execute(RequestContext requestContext) +10
   System.Web.Mvc.<>c__DisplayClassb.<BeginProcessRequest>b__5() +34
   System.Web.Mvc.Async.<>c__DisplayClass1.<MakeVoidDelegate>b__0() +16
   System.Web.Mvc.Async.<>c__DisplayClass8`1.<BeginSynchronous>b__7(IAsyncResult _) +10
   System.Web.Mvc.Async.WrappedAsyncResult`1.End() +50
   System.Web.Mvc.<>c__DisplayClasse.<EndProcessRequest>b__d() +28
   System.Web.Mvc.SecurityUtil.<GetCallInAppTrustThunk>b__0(Action f) +7
   System.Web.Mvc.SecurityUtil.ProcessInApplicationTrust(Action action) +23
   System.Web.Mvc.MvcHandler.EndProcessRequest(IAsyncResult asyncResult) +59
   System.Web.Mvc.MvcHandler.System.Web.IHttpAsyncHandler.EndProcessRequest(IAsyncResult result) +9
   System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +9765901
   System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +155

Views 文件夹中的 Web Config：

<?xml version="1.0"?>

<configuration>
  <configSections>
    <sectionGroup name="system.web.webPages.razor" type="System.Web.WebPages.Razor.Configuration.RazorWebSectionGroup, System.Web.WebPages.Razor, Version=1.0.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35">
      <section name="host" type="System.Web.WebPages.Razor.Configuration.HostSection, System.Web.WebPages.Razor, Version=1.0.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" requirePermission="false" />
      <section name="pages" type="System.Web.WebPages.Razor.Configuration.RazorPagesSection, System.Web.WebPages.Razor, Version=1.0.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" requirePermission="false" />
    </sectionGroup>
  </configSections>

  <system.web.webPages.razor>
    <host factoryType="System.Web.Mvc.MvcWebRazorHostFactory, System.Web.Mvc, Version=3.0.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" />
    <pages pageBaseType="System.Web.Mvc.WebViewPage">
      <namespaces>
        <add namespace="System.Web.Mvc" />
        <add namespace="System.Web.Mvc.Ajax" />
        <add namespace="System.Web.Mvc.Html" />
        <add namespace="System.Web.Routing" />
        <add namespace="DevExpress.Utils" />
        <add namespace="DevExpress.Web.ASPxClasses" />
        <add namespace="DevExpress.Web.ASPxGridView" />
        <add namespace="DevExpress.Web.ASPxGridView.Export" />
        <add namespace="DevExpress.Web.ASPxEditors" />
        <add namespace="DevExpress.Web.ASPxCallbackPanel" />
        <add namespace="DevExpress.Web.ASPxMenu" />
        <add namespace="DevExpress.Web.ASPxNavBar" />
        <add namespace="DevExpress.Web.ASPxPopupControl" />
        <add namespace="DevExpress.Web.ASPxRoundPanel" />
        <add namespace="DevExpress.Web.ASPxSplitter" />
        <add namespace="DevExpress.Web.ASPxTabControl" />
        <add namespace="DevExpress.Web.ASPxTreeView" />
        <add namespace="DevExpress.Web.ASPxUploadControl" />
        <add namespace="DevExpress.Web.ASPxHtmlEditor" />
        <add namespace="DevExpress.Web.ASPxSpellChecker" />
        <add namespace="DevExpress.XtraCharts"/>
        <add namespace="DevExpress.XtraCharts.Web" />
        <add namespace="DevExpress.XtraReports" />
        <add namespace="DevExpress.XtraReports.UI" />
        <add namespace="DevExpress.XtraReports.Web" />
        <add namespace="DevExpress.Web.Mvc" />
        <add namespace="DevExpress.Web.Mvc.UI" />
      </namespaces>
    </pages>
  </system.web.webPages.razor>

  <appSettings>
    <add key="ClientValidationEnabled" value="true"/>
    <add key="UnobtrusiveJavaScriptEnabled" value="true"/>
    <add key="DalManagerType" value="TimeTracker.DalEF.DalManager,TimeTracker.DalEF"/>
    <add key="DalManagerTypeFMS" value="FMSv3.DALEF.DalManager,FMSv3.DALEF" />
    <add key="webpages:Enabled" value="false" />
  </appSettings>

  <system.web>
    <httpHandlers>
      <add path="*" verb="*" type="System.Web.HttpNotFoundHandler"/>
    </httpHandlers>

    <!--
        Enabling request validation in view pages would cause validation to occur
        after the input has already been processed by the controller. By default
        MVC performs request validation before a controller processes the input.
        To change this behavior apply the ValidateInputAttribute to a
        controller or action.
    -->
    <pages
        validateRequest="false"
        pageParserFilterType="System.Web.Mvc.ViewTypeParserFilter, System.Web.Mvc, Version=3.0.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35"
        pageBaseType="System.Web.Mvc.ViewPage, System.Web.Mvc, Version=3.0.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35"
        userControlBaseType="System.Web.Mvc.ViewUserControl, System.Web.Mvc, Version=3.0.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35">
      <controls>
        <add assembly="System.Web.Mvc, Version=3.0.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" namespace="System.Web.Mvc" tagPrefix="mvc" />
      </controls>
    </pages>
  </system.web>

  <system.webServer>
    <validation validateIntegratedModeConfiguration="false" />


    <handlers>
      <remove name="BlockViewHandler"/>
      <add name="BlockViewHandler" path="*" verb="*" preCondition="integratedMode" type="System.Web.HttpNotFoundHandler" />
    </handlers>
  </system.webServer>
</configuration>

Answer 1

案例 1：

重组项目时出现copy+paste 错误。

解决方法：删除@inherits System.Web.Mvc.WebViewPage

案例 2：

如果您将 _ViewStart.cshtml 从 Views 文件夹移至项目的根文件夹。

解决方案：_ViewStart.cshtml 文件只能放在 Views 文件夹中。 （与web.config同级）

案例 3：

如果您将 MVC3 升级到 4.5 框架并遇到此错误。

解决方案：只需将@inherits System.Web.Mvc.ViewStartPage 添加到_ViewStart.cshtml 中