ASP.NET MVC 3 RC AreaRegistration.RegisterAllAreas() and dynamically loaded assemblies

Question

I am currently experimenting with dynamically loaded areas with ASP.NET MVC 3 RC. I\'ve seen it written in many places that this is not what areas are intended for, and (at

Answer 1

1 - Seperate you Mvc Areas into differrent Mvc Projects to be compiled into their own seperate assemblies

2 - Add this to your AssemblyInfo.cs class, to call a method when the application is loaded

[assembly: PreApplicationStartMethod(typeof(PluginAreaBootstrapper), "Init")]

3 - Here's what the Init method looks like when it's invoked during the load

public class PluginAreaBootstrapper
{
    public static readonly List PluginAssemblies = new List();

    public static List PluginNames()
    {
        return PluginAssemblies.Select(
            pluginAssembly => pluginAssembly.GetName().Name)
            .ToList();
    }

    public static void Init()
    {
        var fullPluginPath = Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "Areas");

        foreach (var file in Directory.EnumerateFiles(fullPluginPath, "*Plugin*.dll"))
            PluginAssemblies.Add(Assembly.LoadFile(file));

        PluginAssemblies.ForEach(BuildManager.AddReferencedAssembly);
    }
}

4 - Add a custom RazorViewEngine

public class PluginRazorViewEngine : RazorViewEngine
{
    public PluginRazorViewEngine()
    {
        AreaMasterLocationFormats = new[]
        {
            "~/Areas/{2}/Views/{1}/{0}.cshtml",
            "~/Areas/{2}/Views/{1}/{0}.vbhtml",
            "~/Areas/{2}/Views/Shared/{0}.cshtml",
            "~/Areas/{2}/Views/Shared/{0}.vbhtml"
        };

        AreaPartialViewLocationFormats = new[]
        {
            "~/Areas/{2}/Views/{1}/{0}.cshtml",
            "~/Areas/{2}/Views/{1}/{0}.vbhtml",
            "~/Areas/{2}/Views/Shared/{0}.cshtml",
            "~/Areas/{2}/Views/Shared/{0}.vbhtml"
        };

        var areaViewAndPartialViewLocationFormats = new List
        {
            "~/Areas/{2}/Views/{1}/{0}.cshtml",
            "~/Areas/{2}/Views/{1}/{0}.vbhtml",
            "~/Areas/{2}/Views/Shared/{0}.cshtml",
            "~/Areas/{2}/Views/Shared/{0}.vbhtml"
        };

        var partialViewLocationFormats = new List
        {
            "~/Views/{1}/{0}.cshtml",
            "~/Views/{1}/{0}.vbhtml",
            "~/Views/Shared/{0}.cshtml",
            "~/Views/Shared/{0}.vbhtml"
        };

        var masterLocationFormats = new List
        {
            "~/Views/{1}/{0}.cshtml",
            "~/Views/{1}/{0}.vbhtml",
            "~/Views/Shared/{0}.cshtml",
            "~/Views/Shared/{0}.vbhtml"
        };

        foreach (var plugin in PluginAreaBootstrapper.PluginNames())
        {
            masterLocationFormats.Add(
                "~/Areas/" + plugin + "/Views/{1}/{0}.cshtml");
            masterLocationFormats.Add(
                "~/Areas/" + plugin + "/Views/{1}/{0}.vbhtml");
            masterLocationFormats.Add(
                "~/Areas/" + plugin + "/Views/Shared/{1}/{0}.cshtml");
            masterLocationFormats.Add(
                "~/Areas/" + plugin + "/Views/Shared/{1}/{0}.vbhtml");

            partialViewLocationFormats.Add(
                "~/Areas/" + plugin + "/Views/{1}/{0}.cshtml");
            partialViewLocationFormats.Add(
                "~/Areas/" + plugin + "/Views/{1}/{0}.vbhtml");
            partialViewLocationFormats.Add(
                "~/Areas/" + plugin + "/Views/Shared/{0}.cshtml");
            partialViewLocationFormats.Add(
                "~/Areas/" + plugin + "/Views/Shared/{0}.vbhtml");

            areaViewAndPartialViewLocationFormats.Add(
                "~/Areas/" + plugin + "/Views/{1}/{0}.cshtml");
            areaViewAndPartialViewLocationFormats.Add(
                "~/Areas/" + plugin + "/Views/{1}/{0}.vbhtml");
            areaViewAndPartialViewLocationFormats.Add(
                "~/Areas/" + plugin + "/Areas/{2}/Views/{1}/{0}.cshtml");
            areaViewAndPartialViewLocationFormats.Add(
                "~/Areas/" + plugin + "/Areas/{2}/Views/{1}/{0}.vbhtml");
            areaViewAndPartialViewLocationFormats.Add(
                "~/Areas/" + plugin + "/Areas/{2}/Views/Shared/{0}.cshtml");
            areaViewAndPartialViewLocationFormats.Add(
                "~/Areas/" + plugin + "/Areas/{2}/Views/Shared/{0}.vbhtml");
        }

        ViewLocationFormats = partialViewLocationFormats.ToArray();
        MasterLocationFormats = masterLocationFormats.ToArray();
        PartialViewLocationFormats = partialViewLocationFormats.ToArray();
        AreaPartialViewLocationFormats = areaViewAndPartialViewLocationFormats.ToArray();
        AreaViewLocationFormats = areaViewAndPartialViewLocationFormats.ToArray();
    }
}

5 - Register your Areas from your different Mvc (Area) Projects

namespace MvcApplication8.Web.MyPlugin1
{
    public class MyPlugin1AreaRegistration : AreaRegistration
    {
        public override string AreaName
        {
            get { return "MyPlugin1"; }
        }

        public override void RegisterArea(AreaRegistrationContext context)
        {
            context.MapRoute(
                "MyPlugin1_default",
                "MyPlugin1/{controller}/{action}/{id}",
                new {action = "Index", id = UrlParameter.Optional}
                );
        }
    }
}

Sourcecode and additional references can can be found here:http://blog.longle.io/2012/03/29/building-a-composite-mvc3-application-with-pluggable-areas