Question

Today I noticed that e.g. “System” and “System.Web.Security” are imported in all my razor views, although I did not actively import them. I checked:

• @using directive
• web.config (EDIT: also global web.config)
• AddGlobalImport

EDIT:

It seems these namespace imports are hardwired in the Razor Source Code

https://github.com/ASP-NET-MVC/aspnetwebstack/blob/master/src/System.Web.WebPages.Razor/WebPageRazorHost.cs

    private WebPageRazorHost()
    {
        NamespaceImports.Add("System");
        NamespaceImports.Add("System.Collections.Generic");
        NamespaceImports.Add("System.IO");
        NamespaceImports.Add("System.Linq");
        NamespaceImports.Add("System.Net");
        NamespaceImports.Add("System.Web");
        NamespaceImports.Add("System.Web.Helpers");
        NamespaceImports.Add("System.Web.Security");
        NamespaceImports.Add("System.Web.UI");
        NamespaceImports.Add("System.Web.WebPages");
        NamespaceImports.Add("System.Web.WebPages.Html");

        // ...
    }

It also seems that I can’t disable these by setting a “clear” at the beginning of my web.config:

<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>
            <clear />
            <add namespace="System.Web.Helpers" />
            <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" />
        </namespaces>
    </pages>
</system.web.webPages.razor>

So this issue might be unfixable unless Razor source is changed.

Answer 1

So the answer is: In Razor views some namespaces are always imported. This can’t be disabled in configuration because it is hardwired in the code. These namespaces are:

• System
• System.Collections.Generic
• System.IO
• System.Linq
• System.Net
• System.Web
• System.Web.Helpers
• System.Web.Security
• System.Web.UI
• System.Web.WebPages
• System.Web.WebPages.Html

I am not 100% sure that this is the complete answer, but as long as there is no opposing comment I will accept it.