I'm getting a “Does not implement IController” error on images and robots.txt in MVC2

Question

I'm getting a strange error on my webserver for seemingly every file but the .aspx files.

Here is an example. Just replace '/robots.txt' with any .jpg name or .gif or whatever and you'll get the idea:

The controller for path '/robots.txt' was not found or does not implement IController.

I'm sure it's something to do with how I've setup routing but I'm not sure what exactly I need to do about it.

Also, this is a mixed MVC and WebForms site, if that makes a difference.

Answer 1

You can ignore robots.txt and all the aspx pages in your routing.

routes.IgnoreRoute("{*allaspx}", new {allaspx=@".*\.aspx(/.*)?"});
routes.IgnoreRoute("{*robotstxt}", new {robotstxt=@"(.*/)?robots.txt(/.*)?"});

You might want to ignore the favicon too.

routes.IgnoreRoute("{*favicon}", new {favicon=@"(.*/)?favicon.ico(/.*)?"});

You can adjust the regular expression to exclude paths.

Haacked from the source.

Answer 2

The ignore route given above didn't work for me but I found a similar one that did:

routes.IgnoreRoute("{*staticfile}", new { staticfile = @".*\.(css|js|gif|jpg)(/.*)?" });

Answer 3

This error could also happen if inside a view in your area, you use the Html.Action helper. This helper will always use the area as a prepend, unless you specifically tell it not to. E.g.,

@Html.Action("Main", "Navigation", new { area = string.Empty })

Answer 4

I found another solution too... While I don't think I'll use it, it's worth showing here in the answers:

The following should (in theory) ignore looking for controllers for anything with a '.' in it.

routes.MapRoute(
    "Default",                                              // Route name
    "{controller}/{action}/{id}",                           // URL with parameters
    new { controller = "Home", action = "Index", id = "" },  // Parameter defaults
    new { controller = @"[^\.]*" }                          // Parameter contraints.
);

Answer 5

Do you still have:

routes.IgnoreRoute("{resource}.axd/{*pathInfo}");

... in your Global.asax.cs?

MVC puts it there by default, and it's supposed to handle this.

If you do, then the problem may be how you're mixing MVC and WebForms.

Answer 6

I encountered this error when I request resources that did not exist.

Specifically, I was requesting a custom IE css file:

<!--[if lt IE 8]>@Styles.Render("~/Content/ie7.css")<![endif]-->

(These are condition comments, interpreted by IE)

However, the actual resource existed on ~/Content/ie/ie7.css.

So, without any modifications to the routing, the error was solved by using the correct url of the resource.