If I create a new empty MVC application, add a controller and a view and then run I get a compile error which appears to be from IISExpress as it doesn't show as an error in Visual Studio.
Server Error in '/' Application.
Compilation Error
Description: An error occurred during the compilation of a resource required to service this request. Please review the following specific error details and modify your source code appropriately.
Compiler Error Message: BC30451: 'ViewData' is not declared. It may be inaccessible due to its protection level.
Source Error:
Line 1: @Code
Line 2: ViewData("Title") = "Index"
Line 3: End Code
The Views web.config appears to be correct as it contains the various required namespace:
<?xml version="1.0"?>
<configuration>
<configSections>
<sectionGroup name="system.web.webPages.razor" type="System.Web.WebPages.Razor.Configuration.RazorWebSectionGroup, System.Web.WebPages.Razor, Version=3.0.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35">
<section name="host" type="System.Web.WebPages.Razor.Configuration.HostSection, System.Web.WebPages.Razor, Version=3.0.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" requirePermission="false" />
<section name="pages" type="System.Web.WebPages.Razor.Configuration.RazorPagesSection, System.Web.WebPages.Razor, Version=3.0.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" requirePermission="false" />
</sectionGroup>
</configSections>
<system.web.webPages.razor>
<host factoryType="System.Web.Mvc.MvcWebRazorHostFactory, System.Web.Mvc, Version=5.1.0.0, 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="MVCAjaxWorkbench" />
</namespaces>
</pages>
</system.web.webPages.razor>
<appSettings>
<add key="webpages:Enabled" value="false" />
</appSettings>
<system.webServer>
<handlers>
<remove name="BlockViewHandler"/>
<add name="BlockViewHandler" path="*" verb="*" preCondition="integratedMode" type="System.Web.HttpNotFoundHandler" />
</handlers>
</system.webServer>
</configuration>
and the main web.config appears to be correct as well:
<?xml version="1.0" encoding="utf-8"?>
<!--
For more information on how to configure your ASP.NET application, please visit
http://go.microsoft.com/fwlink/?LinkId=301880
-->
<configuration>
<appSettings>
<add key="webpages:Version" value="3.0.0.0"/>
<add key="webpages:Enabled" value="false"/>
<add key="ClientValidationEnabled" value="true"/>
<add key="UnobtrusiveJavaScriptEnabled" value="true"/>
</appSettings>
<system.web>
<compilation debug="true" targetFramework="4.5.1"/>
<httpRuntime targetFramework="4.5.1"/>
</system.web>
<runtime>
<assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
<dependentAssembly>
<assemblyIdentity name="System.Web.Optimization" publicKeyToken="31bf3856ad364e35"/>
<bindingRedirect oldVersion="1.0.0.0-1.1.0.0" newVersion="1.1.0.0"/>
</dependentAssembly>
<dependentAssembly>
<assemblyIdentity name="WebGrease" publicKeyToken="31bf3856ad364e35"/>
<bindingRedirect oldVersion="1.0.0.0-1.5.2.14234" newVersion="1.5.2.14234"/>
</dependentAssembly>
<dependentAssembly>
<assemblyIdentity name="System.Web.Helpers" publicKeyToken="31bf3856ad364e35"/>
<bindingRedirect oldVersion="1.0.0.0-3.0.0.0" newVersion="3.0.0.0"/>
</dependentAssembly>
<dependentAssembly>
<assemblyIdentity name="System.Web.WebPages" publicKeyToken="31bf3856ad364e35"/>
<bindingRedirect oldVersion="1.0.0.0-3.0.0.0" newVersion="3.0.0.0"/>
</dependentAssembly>
<dependentAssembly>
<assemblyIdentity name="System.Web.Mvc" publicKeyToken="31bf3856ad364e35"/>
<bindingRedirect oldVersion="1.0.0.0-5.1.0.0" newVersion="5.1.0.0"/>
</dependentAssembly>
</assemblyBinding>
</runtime>
</configuration>
I think that something has gone wrong with my installation of IISExpress. I've reviewed the options for using IIS instead of IISExpress and I really would much prefer to stick with IISExpress but simply reinstalling it has made no difference. My next step is to try reinstalling Visual Studio but I'd rather avoid that if possible as it tends to have side effects of its own.
How can I repair my IISExpress installation so that it functions correctly with Visual Studio?
I actually managed to get this working myself by doing the following:
Copy Local = True
in the properties of the references for System.Web.MVC (following some of the answers in this question)I can't tell which of those was the crucial step although I suspect it was setting Copy Local = True
but an MS update appears to be the source of the problem.