Custom HttpHandler not firing, returning 404 in ASP.NET MVC Application

Question

I don't know if it is relevant that this is happening in an MVC website but thought I'd mention it anyway.

In my web.config I have these lines:

<add verb="*" path="*.imu" type="Website.Handlers.ImageHandler, Website, Version=1.0.0.0, Culture=neutral" />

in the Website project I have a folder named Handlers which contains my ImageHandler class. It looks like this (I have removed the processrequest code)

using System;
using System.Globalization;
using System.IO;
using System.Web;

namespace Website.Handlers
{
    public class ImageHandler : IHttpHandler
    {
        public virtual void ProcessRequest(HttpContext context)
        {
            //the code here never gets fired
        }

        public virtual bool IsReusable
        {
            get { return true; }
        }
    }
}

If I run my website and go to /something.imu it just returns a 404 error.

I am using Visual Studio 2008 and trying to run this on the ASP.Net development server.

I've been looking for several hours and had it working in a seperate empty website. So I don't understand why it won't work inside an existing website. There are no other references to the *.imu path btw.

Answer 1

I suspect that this has everything to do with the fact that you are using MVC, as basically it takes control of all incoming requests.

I suspect you will have to use the routing table, and possibly create a new routing handler. I haven't done this myself but something like this might work:

void Application_Start(object sender, EventArgs e) 
{
    RegisterRoutes(RouteTable.Routes);
}

public static void RegisterRoutes(RouteCollection routes)
{
    routes.Add(new Route
    (
         "{action}.imu"
         , new ImageRouteHandler()
    ));
}

and then the ImageRouteHandler class will then return your custom ImageHttpHandler, although from looking at examples on the web it might be better to chance that so it implements MvcHandler, rather than straight IHttpHandler.

Edit 1: As per Peter's comment, you can also ignore the extension by using the IgnoreRoute method:

public static void RegisterRoutes(RouteCollection routes)
{
  routes.IgnoreRoute("{resource}.imu/{*pathInfo}");
}