ASP MVC - Using HTML Helpers in a View class library - asp.net-mvc-5

Question

I am working on a MVC Solution divided in separated assemblies, one of them containing only the views.
The problem I have is about using Html Helpers (written in HTML, not C# classes) in my views ; Razor Intellisense does not find any of my helpers. The helper file (HeaderHelper.cshtml) is located in my App_Code folder.
Here is an example of a Helper I want to use :
<!-- PAGE HEADERS HELPERS -->
#helper HelperPageHeader(String title)
{
<div class="page-header text-center">
<h3>#title</h3>
</div>
}
And here is how I want to call my helper in my view :
#HeaderHelper.HelperPageHeader("Test HeaderHelper")
<div>
<!-- HTML -->
</div>
But I get the compilation error "The name HeaderHelper does not exist in the current context".
I believe there is no way to set a namespace for my HTML Helper.
Perhaps this issue is related to something wrong in my web.config file, here is its content :
<?xml version="1.0" encoding="utf-8"?>
<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=5.0.0.0, 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="System.Web.WebPages" />
<add namespace="ViewsLibrary" />
</namespaces>
</pages>
</system.web.webPages.razor>
<appSettings>
<add key="webpages:Version" value="3.0.0.0" />
<add key="webpages:Enabled" value="false" />
<add key="MvcSiteMapProvider_UseExternalDIContainer" value="false" />
<add key="MvcSiteMapProvider_ScanAssembliesForSiteMapNodes" value="true" />
<add key="MvcSiteMapProvider_IncludeAssembliesForScan" value="ViewsLibrary" />
</appSettings>
<system.web>
<compilation targetFramework="4.5">
<assemblies>
<add assembly="MvcSiteMapProvider, Version=4.6.18.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" />
<add assembly="System.Data.Entity.Design, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" />
<add assembly="System.Core, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" />
<add assembly="System.Web.Abstractions, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" />
<add assembly="System.Web.Helpers, Version=3.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" />
<add assembly="System.Web.Mvc, Version=5.2.3.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" />
<add assembly="System.Web.Mvc.Html, Version=5.2.3.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" />
<add assembly="System.Web.Optimization, Version=1.1.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" />
<add assembly="System.Web.Razor, Version=3.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" />
<add assembly="System.Web.Routing, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" />
<add assembly="System.Data.Linq, Version=4.0.0.0, Culture=neutral, PublicKeyToken=B77A5C561934E089" />
<add assembly="System.Web.WebPages, Version=3.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" />
<add assembly="System.Web.WebPages.Razor, Version=3.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" />
<add assembly="Microsoft.AspNet.Identity, Version=2.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" />
</assemblies>
</compilation>
<httpRuntime targetFramework="4.5" />
<pages>
<namespaces>
<add namespace="MvcSiteMapProvider.Web.Html" />
<add namespace="MvcSiteMapProvider.Web.Html.Models" />
</namespaces>
</pages>
</system.web>
<system.webServer>
<handlers>
<remove name="BlockViewHandler" />
<add name="BlockViewHandler" path="*" verb="*" preCondition="integratedMode" type="System.Web.HttpNotFoundHandler" />
</handlers>
<modules>
<remove name="UrlRoutingModule-4.0" />
<add name="UrlRoutingModule-4.0" type="System.Web.Routing.UrlRoutingModule" />
</modules>
</system.webServer>
<runtime>
<assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
<dependentAssembly>
<assemblyIdentity name="WebGrease" publicKeyToken="31bf3856ad364e35" culture="neutral" />
<bindingRedirect oldVersion="0.0.0.0-1.5.2.14234" 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="1.0.0.0-5.2.3.0" newVersion="5.2.3.0" />
</dependentAssembly>
</assemblyBinding>
</runtime>
</configuration>
Any ideas ? Thanks in advance for your help !

Answer 1

The #helper directive was removed since beta 4 because it imposed too many restrictions on other Razor features: https://github.com/aspnet/Razor/issues/281.