WebForms and Razor View Engine Example

BaseViewEngine.cs

public class BaseViewEngine : RazorViewEngine
{
    protected BaseViewEngine()
    {
        this.AreaViewLocationFormats = new string[4]
        {
            "~/Areas/{2}/Views/{1}/{0}.cshtml",
            "~/Areas/{2}/Views/{1}/{0}.aspx",
            "~/Areas/{2}/Views/{1}/{0}.ascx",
            "~/Areas/{2}/Views/Shared/{0}.cshtml",
            "~/Areas/{2}/Views/Shared/{0}.aspx",
            "~/Areas/{2}/Views/Shared/{0}.ascx"
        };
        this.AreaMasterLocationFormats = new string[4]
        {
            "~/Areas/{2}/Views/{1}/{0}.cshtml",
            "~/Areas/{2}/Views/{1}/{0}.master",
            "~/Areas/{2}/Views/Shared/{0}.cshtml",
            "~/Areas/{2}/Views/Shared/{0}.master"
        };
        this.ViewLocationFormats = new string[4]
        {
            "~/Views/{1}/{0}.cshtml",
            "~/Views/{1}/{0}.aspx",
            "~/Views/{1}/{0}.ascx",
            "~/Views/Shared/{0}.cshtml",
            "~/Views/Shared/{0}.aspx",
            "~/Views/Shared/{0}.ascx"
        };
        this.MasterLocationFormats = new string[4]
        {
            "~/Views/{1}/{0}.cshtml",
            "~/Views/{1}/{0}.master",
            "~/Views/Shared/{0}.cshtml",
            "~/Views/Shared/{0}.master"
        };
        this.PartialViewLocationFormats = this.ViewLocationFormats;
        this.AreaPartialViewLocationFormats = this.AreaViewLocationFormats;
        FileExtensions = new[] { "cshtml", "aspx", "ascx", "master" };
    }

    protected override IView PartialView(ControllerContext context, string path)
        => IsRazor(path) ? base.CreatePartialView(context, path) : WebFormsView(context, path);

    protected override IView View(ControllerContext context, string path, string masterPath)
        => IsRazor(path) ? base.CreateView(context, path, masterPath) : WebFormsView(context, path, masterPath);

    private IView WebFormsView(ControllerContext context, string path, string masterPath = null)
        => new WebFormView(context, path, masterPath, ViewPageActivator);
  
    private static bool IsRazor(string path) => path.EndsWith(".cshtml");
}

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=2.0.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35"> 
       <section name="host" type="System.Web.WebPages.Razor.Configuration.HostSection, System.Web.WebPages.Razor, Version=2.0.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" requirePermission="false" /> 
       <section name="pages" type="System.Web.WebPages.Razor.Configuration.RazorPagesSection, System.Web.WebPages.Razor, Version=2.0.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" requirePermission="false" /> 
     </sectionGroup> 
   </configSections> 
   
   <system.web.webPages.razor> 
   <host factoryType="System.Web.Mvc.MvcWebRazorHostFactory, System.Web.Mvc, Version=4.0.0.0, 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 any namespaces you need included here -->
       </namespaces> 
     </pages> 
   </system.web.webPages.razor> 

  <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=2.0.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35"
        pageBaseType="System.Web.Mvc.ViewPage, System.Web.Mvc, Version=2.0.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35"
        userControlBaseType="System.Web.Mvc.ViewUserControl, System.Web.Mvc, Version=2.0.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35">
      <controls>
        <add assembly="System.Web.Mvc, Version=2.0.0.0, 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>