Where can I find System.Web.Helpers, System.Web.WebPages, and System.Web.Razor?

Solution 1:

You will find these assemblies in the Extensions group under Assemblies in Visual Studio 2010, 2012 & 2013 (Reference Manager)

Solution 2:

To sum up all of the options for VS 2017, WebHelpers was installed by installing MVC in previous versions of Visual Studio. If you're getting this error, you probably don't have the older versions of VS installed anymore.

So, installing the Microsoft.AspNet.MVC NuGet package will require Microsoft.AspNet.WebPages and Microsoft.AspNet.Razor, and the Microsoft.AspNet.WebPages includes System.Web.Helpers.dll.

If you've got direct references to System.Web.Mvc.dll and you don't want to use NuGet for MVC, you can get the Microsoft.AspNet.WebPages NuGet, or there are some other NuGet packages that only contain System.Web.Helpers.dll, like the microsoft-web-helpers or System-Web-Helpers.dllpackages.

There appear to be 2 versions of System.Web.Helpers.dll, one for .Net 4.0 and one for 4.5. Choosing the correct version of MVC or AspNet.WebPages will ensure you get the right one.

Solution 3:

As for VS2017 I didn't find it in "extensions", there's a Nuget package called "microsoft-web-helpers" that seems to be equivalent to System.Web.Helpers.