Razor HtmlHelper Extensions or other namespaces for views Not Found

Question

I don t know if this was happening in the PR or Beta  but if I create an extension method on HtmlHelper  it is not recognized in a Razor powered page  namespace SomeNamespace Extensions       public static class HtmlExtensions           public static string Foo this HtmlHelper html                return  quot Foo quot                      I added it to the  lt Namespaces gt  section in Web config   lt pages gt     lt namespaces gt       lt add namespace  quot System Web Mvc quot    gt       lt  -- snip -- gt       lt add namespace  quot SomeNamespace Extensions quot   gt     lt  namespaces gt   lt  pages gt   But it throws a compile error when trying to view the page   Html Foo    If I recreate the page with WebForms it works fine  What s the deal  Workaround If I include  using SomeNamespace Extensions in my Razor view  then it works  but I d much rather just have it in Web config

User · Answer

As the accepted answer suggests you can add  using  to all views by adding to  section of config file   But for a single view you could just use      using SomeNamespace Extensions

User · Answer

In my case use VS 2013  and It s not support MVC 3 natively  even of you change   Views web config   https   stackoverflow com a 28155567 1536197

User · Answer

I found that putting this section in my web config for each view folder solved it    lt runtime gt           lt assemblyBinding xmlns  urn schemas-microsoft-com asm v1  gt               lt dependentAssembly gt                   lt assemblyIdentity name  System Web Mvc  publicKeyToken  31bf3856ad364e35    gt                   lt bindingRedirect oldVersion  1 0 0 0-2 0 0 0  newVersion  4 0 0 0    gt               lt  dependentAssembly gt           lt  assemblyBinding gt       lt  runtime gt

User · Answer

This error tells you that you do not have the razor engine properly associated with your project     Solution  In the Solution Explorer window right click on your web project and select  Manage Nuget Packages     then install  Microsoft ASP NET Razor    This will make sure that the properly package is installed and it will add the necessary entries into your web config file

User · Answer

Since the Beta  Razor uses a different config section for globally defining namespace imports  In your Views Web config file you should add the following    lt configSections gt     lt 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  gt       lt 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    gt       lt 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    gt     lt  sectionGroup gt   lt  configSections gt    lt system web webPages razor gt     lt host factoryType  System Web Mvc MvcWebRazorHostFactory  System Web Mvc  Version 3 0 0 0  Culture neutral  PublicKeyToken 31BF3856AD364E35    gt     lt pages pageBaseType  System Web Mvc WebViewPage  gt       lt namespaces gt         lt add namespace  System Web Mvc    gt         lt add namespace  System Web Mvc Ajax    gt         lt add namespace  System Web Mvc Html    gt         lt add namespace  System Web Routing    gt         lt  -- Your namespace here -- gt       lt  namespaces gt     lt  pages gt   lt  system web webPages razor gt    Use the MVC 3 upgrade tool to automatically ensure you have the right config values   Note that you might need to close and reopen the file for the changes to be picked up by the editor

User · Answer

Since ASP NET MVC 3 RTM is out there is no need for config section for Razor  And these sections can be safely removed

User · Answer

I had this same error in an MVC 4 application using Razor  In an attempt to clean up the web config files  I removed the two webpages  configuration values    lt appSettings gt     lt add key  webpages Version  value  2 0 0 0    gt     lt add key  webpages Enabled  value  false    gt    Once I restored these configuration values  the pages would compile correctly and the errors regarding the  Partial   extension method disappeared

User · Answer

I had this issue in VS 2015  The following solved it for me   Find  webpages Version  in the appsettings and update it to version 3 0 0 0  My web config had   lt add key  webpages Version  value  2 0 0 0    gt    and I updated it to   lt add key  webpages Version  value  3 0 0 0    gt

[asp.net-mvc-3] Razor HtmlHelper Extensions (or other namespaces for views) Not Found

Examples related to asp.net-mvc-3

Examples related to extension-methods

Examples related to razor

Examples related to html-helper