Controller action "Index" not invoked with default setting - asp.net-mvc

Question

I have a ASP.NET web application project, I implemented a WebApi controller and now proceeding with a MVC controller.
I've added a new MVC controller (eg. "Test") and selected to add it with "empty read and write actions".
The controller is created with various CRUD methods, however the Index action is behaving unexpectedly.
By default the Index action does not take any arguments:
public ActionResult Index()
{
return View();
}
Now if I try to invoke this method using url "/Test/Index", the method is not being called.
But if I type url "/Test/Index/1" the Index action is run.
It looks to me that its related to routing so I checked the RouteConfig class which looks like:
public static void RegisterRoutes(RouteCollection routes)
{
routes.IgnoreRoute("{resource}.axd/{*pathInfo}");
routes.MapRoute(
name: "Default",
url: "{controller}/{action}/{id}",
defaults: new { controller = "Home", action = "Index", id = UrlParameter.Optional }
);
}
Id is set to optional and my understanding is I should not be required to provide a parameter value in Index method?
I created another project and checked this behavior and it works fine.
So wondering what in this project making MVC controller behaving differently?
Is mixing WebApi controllers with MVC controllers having some side effect (making it a special case)?
Let me know if you need any information to answer this question.
Update:
I did modify the WebApiConfig for making API controller work as per my requirement, it looks like this:
public static void Register(HttpConfiguration config)
{
config.Routes.MapHttpRoute(
name: "DefaultApi",
routeTemplate: "{controller}/{action}",
defaults: new { controller = "iclock", action = "cdata" }
);
}
I could not understand why it affect the MVC controller route? I got it now with answers provided.
Update 2:
The problem in this case is I can not (or can I?) prefix api in web api route as a third party device is sending GET and POST request using a fixed url, like following:
GET /iclock/cdata?SN=xxxxxx&options=all&pushver=2.0.2&language=XX
GET /iclock/cdata?SN=xxxxxx&type=time
POST /iclock/cdata?SN=123456&table=ATTLOG&Stamp=2011-04-05T17:40:20
I achieved above request handling functionality making changes into the WebApiConfig route. Now need a front end UI for which I am developing a MVC controller with CRUD operation.
What should be ideal approach in this case?

Answer 1

It could be when you navigate to Test/Index it doesn't know if it should use the web route where there is an optional "id" or the api route where there is no "id". If possible I would prefix your Web API routes, such as "api/{controller}/{action}" as described in the MVC Web API template.
For your second example, applications that access the API would simple prefix the URLs with "api/". If they are using the URLs you specified and cannot be changed, then I think you may be stuck because when the request comes in there is still the problem of not knowing which route to use.
If the URLs can be changed, as mentioned above, simple prefix with "api/".
EDIT: Updated my answer based on the extra information/code-snippet provided.
EDIT: Updated again

Answer 2

Did you look in WebApiConfig instead of RouteConfig in App_Start
public static void Register(HttpConfiguration config)
{
config.Routes.MapHttpRoute(
name: "DefaultApi",
routeTemplate: "api/{controller}/{id}",
defaults: new { id = RouteParameter.Optional }
);
}

Answer 3

You have a conflict in your routing table. Your Web API routing table is now the same as your standard MVC routing table. Your Web API routing table (the one that is initialized with MapHttpRoute should be declared as: routeTemplate: "api/{controller}/{id}". Also, you shouldn't have modified the Web API route. It is not cast in stone that it must be api/{controller}/{id}, but there is a certain convention that you should follow. Try reseting your routes to be like the following and then try again:
public static class WebApiConfig
{
public static void Register(HttpConfiguration config)
{
config.Routes.MapHttpRoute(
name: "DefaultApi",
routeTemplate: "api/{controller}/{id}",
defaults: new { id = RouteParameter.Optional }
);
}
}
public class RouteConfig
{
public static void RegisterRoutes(RouteCollection routes)
{
routes.IgnoreRoute("{resource}.axd/{*pathInfo}");
routes.MapRoute(
name: "Default",
url: "{controller}/{action}/{id}",
defaults: new { controller = "Home", action = "Index", id = UrlParameter.Optional }
);
}
}
So, first reset to normal routing configuration and test. After that make changes slowly and follow the result.