In my MVC application I have a default route defined:
routes.MapRoute(
"Default", // Route name
"{controller}/{action}/{id}", // URL with parameters
new { controller = "Home", action = "Index", id = UrlParameter.Optional },
new []{ "Demo.Controllers" }
);
I created a new Area called Admin and it added a route to in the AdminAreaRegistration class:
public override void RegisterArea(AreaRegistrationContext context)
{
context.MapRoute(
"Admin_default",
"Admin/{controller}/{action}/{id}",
new { action = "Index", controller = "Home", id = UrlParameter.Optional }
);
}
In my main _Layout file I tried to do the following:
#Html.RouteLink("Admin", "Admin_default")
It only works in certain cases (such as if I'm already in an Admin page). If I am in the /Home/About section of my site, then the URL gets generated like so:
/Admin/Home/About
If I am in my Index action of the Home controller (in the main area, not admin) then the URL gets generated like so:
/Admin
Why doesn't RouteLink work like I think it should using Areas in MVC?
#Html.RouteLink("Admin", "Admin_default") this route uses the route with the name of Admin_default so it will always use that route to generate the url.
#Html.RouteLink("Admin", "Admin_default", new { controller = "Home", action = "Index" })
When you don't specify stuff like route values most of MVC uses the values that currently exist. In this case since the action and controller values are null it looks at the RouteValues and checks to see if they're there and if they're found they use the values found there instead.
This is sometimes helpful. For instance if you want {id} to be populated with the same value that was used on the page.
Url: /home/edit/1701
#Html.RouteLink("Refresh", "Default") would result in the same exact url - you can specify overrides if you want.
I would also suggest not naming your routes. You can force yourself to do this by passing null to the route name arg when creating it.
public override void RegisterArea(AreaRegistrationContext context)
{
context.MapRoute(null,
"Admin/{controller}/{action}/{id}",
new { action = "Index", controller = "Home", id = UrlParameter.Optional }
);
}
You can then use RouteLink like so:
#Html.RouteLink("Admin",
new { controller = "Home", action = "Index", area = "Admin" })
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Wish I could say I came up with the idea. Learned this from Steve Sanderson's MVC book. There are a ton of method overloads that take a route name as a parameter (RouteLink, but also RedirectToRoute and others). Not using route names forces you to use other overloads of those methods, which IMO are more intuitive and easier to "get right".
Naming your routes is not recommended since it creates dependencies in your view towards the existing routes. I suggest using a null value
Related
Problem
For the default route MVC is returning a "Multiple types were found that match the controller named 'admin'." error instead of a 404 not found. There is no admin controller in that namespace.
We're using MVC 5.2.2.
Background
We're using MVC areas. Two areas contain an "admin" controller. When you use the full path as defined in their respective routes, both areas' admin controllers are accessible and work correctly.
The problem arises when you try to access "admin" from the default route. Admin does not exist in that context, so we'd expect a 404 not found, however instead we receive:
Multiple types were found that match the controller named 'admin'. This can happen
if the route that services this request ('{controller}/{action}/{id}') does not
specify namespaces to search for a controller that matches the request. If this
is the case, register this route by calling an overload of the 'MapRoute' method
that takes a 'namespaces' parameter.
The request for 'admin' has found the following matching controllers:
DMP.Stock.Web.Controllers.AdminController
DMP.Inventory.Web.Controllers.AdminController
Here is our default route and two area routes:
public static void RegisterRoutes(RouteCollection routes)
{
// Default Route
routes.MapRoute(
name: "Default",
url: "{controller}/{action}/{id}",
defaults: new { controller = "Home", action = "Index", id = UrlParameter.Optional },
namespaces: new string[] { "DMP.Core.Web.Controllers" }
);
}
public override void RegisterArea(AreaRegistrationContext context)
{
// Area 1: Stock
context.MapRoute(
name: "Stock_default",
url: "Stock/{controller}/{action}/{id}",
defaults: new { controller = "Home", action = "Index", id = UrlParameter.Optional },
namespaces: new string[] { "DMP.Stock.Web.Controllers" }
);
}
public override void RegisterArea(AreaRegistrationContext context)
{
// Area 2: Inventory
context.MapRoute(
"Inventory_default",
"Inventory/{controller}/{action}/{id}",
new { controller = "Home", action = "Index", id = UrlParameter.Optional },
namespaces: new string[] { "DMP.Inventory.Web.Controllers" }
);
}
/Stock/Admin/Index works correctly.
/Inventory/Admin/Index works correctly.
/Admin/ does not work correctly (expect: 404 not found, receive "multiple controllers" error).
The errors suggests we add namespaces to our routes, but as you can see above both the default and the two areas already have a namespace definition. The default route points at a namespace without any "admin" controllers in it.
I think MVC is trying to be "helpful" by searching for possible controllers that could match the requested URL. Is there any way I can turn that off?
I've been able to resolve this issue myself. Here is the solution I found:
// Default Route
routes.MapRoute(
name: "Default",
url: "{controller}/{action}/{id}",
defaults: new { controller = "Home", action = "Index", id = UrlParameter.Optional },
namespaces: new string[] { "DMP.Core.Web.Controllers" }
).DataTokens["UseNamespaceFallback"] = false;
Note the addition of .DataTokens["UseNamespaceFallback"] = false; this is what resolves the issue. There isn't very much (any?) documentation on this functionality, however I found it while reading the MVC source code, specifically within DefaultControllerfactory (the source of this issue).
After you know to google for "UseNamespaceFallback" you can find a few blog posts and questions where people have had a similar issue and resolved it the same way. However I can find no MSDN documentation on this DataToken.
So I know google can penalize a site if you have the same content on multiple urls... unfortunately, in MVC this is too common i can have example.com/, example.com/Home/ and example.com/Home/Index and all three urls would take me to the same page... so how do I make sure that whenever Index is in the url, that it redirects to the same without the Index and of course the same thing with the Home
Perhaps this little library may be useful for you.
This library is not very convinient in your case, but it should work.
var route = routes.MapRoute(name: "Default",
url: "{controller}/{action}/{id}",
defaults: new { controller = "Home", action = "Index", id = UrlParameter.Optional });
routes.Redirect(r => r.MapRoute("home_index", "/home/index")).To(route);
routes.Redirect(r => r.MapRoute("home", "/home")).To(route);
The way I handle this is for default pages like Index is to simply create an explicit route for only one of them. I.e. "example.com/People" would be the route for People/Index, and there would be no valid page at the url "/example.com/People/Index".
The Home example is unique in that it has potentially three different URLs. Again in this case I'd simply create a route for "example.com" for that Index action, and not support the other two urls. In other words, you would never link to the other forms of the URL, so their absence should never cause a problem.
We use a Nuget package called AttributeRouting to support this. When you specifiy a GET route for a page, it overrides the defaults for MVC.
Using AttributeRouting usually you'd map the index to [GET("")] but for the special case of Home where you also want to also support the root URL that omits the controller name , I think you'd also add an additional attribute with IsAbsoluteUrl:
public class HomeController : BaseController
{
[GET("")]
[GET("", IsAbsoluteUrl = true)]
public ActionResult Index()
{...
So I found a way to do it without any external Library...
In my RouteConfig I had to add these two routes at the top, just below the IgnoreRoute
routes.MapRoute(
"Root",
"Home/",
new { controller = "Redirect", action = "Home" }
);
routes.MapRoute(
"Index",
"{action}/Index",
new { controller = "Redirect", action = "Home" }
);
Then I had to create a new Controller called Redirect and I created a method for each of my other Controllers like this:
public class RedirectController : Controller
{
public ActionResult Home()
{
return RedirectPermanent("~/");
}
public ActionResult News()
{
return RedirectPermanent("~/News/");
}
public ActionResult ContactUs()
{
return RedirectPermanent("~/ContactUs/");
}
// A method for each of my Controllers
}
That's it, now my site looks legit. No more Home, no more Index in my URLs, this of course has the limitation of not being able to accept parameters to any of the Index methods of your Controllers though if it was really necessary, you should be able to tweak this to achieve what you want.
Just an FYI, if you want to pass an argument to your Index Action, then you can add a third route like this:
routes.MapRoute(
name: "ContactUs",
url: "ContactUs/{id}/{action}",
defaults: new { controller = "ContactUs", action = "Index", id = UrlParameter.Optional }
);
This will create a URL like this: /ContactUs/14
I have a web site that had no areas registered. Then I registered an area called "MyNewArea".
Now my default website links like blogs etc no longer work.
So I now have an areas folder with a single area in it and the default folders when I created the project in the first place.
In my area AreaRegistration class I have;
public override void RegisterArea(AreaRegistrationContext context)
{
context.MapRoute(
"MyArea_default",
"{controller}/{action}/{id}",
new { action = "Index", id = UrlParameter.Optional }
);
}
but this looks like it conflicts with the default one of
routes.MapRoute(
"Default", // Route name
"{controller}/{action}/{id}", // URL with parameters
new { controller = "Home", action = "Index", id = UrlParameter.Optional } // Parameter defaults
);
What do I need to do to get the area to work with the default site and controllers?
You're right, that mapped route would conflict (in the sense of "conflict" as in it will be matched first). You would need to alter your mapped Area route to be something like:
context.MapRoute(
"MyArea_default",
"MyArea/{controller}/{action}/{id}",
new { controller = "MyAreaController", action = "Index", id = UrlParameter.Optional }
);
The reason why your URLs broke after you added this Area (and in turn the Area route), it used your Area route for handling that didn't exist in your MyArea Area.
Change the new area route table to be:
context.MapRoute(
"MyArea_default",
"MyNewArea/{action}/{id}",
new { controller = "MyNewArea", action = "Index", id = UrlParameter.Optional }
);
In MVC3, I have the following areas:
Mobile
Sandbox
Then i route maps like this:
context.MapRoute(
"Sandbox_default",
"Sandbox/{controller}/{action}/{id}",
new { controller = "SandboxHome", action = "Index", id = UrlParameter.Optional }
and
context.MapRoute(
"Mobile_default",
"Mobile/{controller}/{action}/{id}",
new { controller = "MobileHome", action = "Index", id = UrlParameter.Optional }
);
The problem is this gives urls like:
http://localhost:58784/Mobile/MobileHome
and
http://localhost:58784/Sandbox/SandboxHome
But I want it like this:
http://localhost:58784/Mobile/Home
http://localhost:58784/Sandbox/Home
The problem is when I rename the SandboxHome-Controller to Home, and the MobileHome-Controller to Home, which would give the desired URLs, it won't compile, saying it has two classes for HomeController.
How can I have the same controller name in different areas ?
Yes.
As explained by this blog post: http://haacked.com/archive/2010/01/12/ambiguous-controller-names.aspx
Assuming you have a call to RegisterAllAreas and the AreaRegistration files generated by Visual Studio. All you need to do is the namespace on the default route in global ASAX to prevent conflicts.
//Map routes for the main site. This specifies a namespace so that areas can have controllers with the same name
routes.MapRoute(
"Default",
"{controller}/{action}/{id}",
new { controller = "Home", action = "Index", id = UrlParameter.Optional },
new[]{"MyProject.Web.Controllers"}
);
As long as you keep the Area controllers within their own namespaces. This will work.
Yes it is but you'll have to change your routing:
context.MapRoute(
"Default",
"{area}/{controller}/{action}/{id}",
new { area = "Mobile", controller = "Home", action = "Index", id = UrlParameter.Optional }
);
You could as well keep both routes but don't forget to define area in your defaults.
Important
Of course you must keep controllers in their own area namespaces:
namespace MyApp.Areas.Mobile.Controllers
{
public class HomeController : Controller
{
...
}
}
namespace MyApp.Areas.Sandbox.Controllers
{
public class HomeController : Controller
{
...
}
}
Check this link on MSDN and see the walktrough. And don't forget to also check out this MSDN article that talks about area registration, because you will have to call RegisterAllAreas() method.
And since you still want to keep original non-area controllers, you should also read this Phil Haack's article how to do just that (Credit should go to #Rob in his answer for pointing to this blog post first).
I'm new to MVC (and ASP.Net routing). I'm trying to map *.aspx to a controller called PageController.
routes.MapRoute(
"Page",
"{name}.aspx",
new { controller = "Page", action = "Index", id = "" }
);
Wouldn't the code above map *.aspx to PageController? When I run this and type in any .aspx page I get the following error:
The controller for path '/Page.aspx' could not be found or it does not implement the IController interface.
Parameter name: controllerType
Is there something I'm not doing here?
I just answered my own question. I had
the routes backwards (Default was
above page).
Yeah, you have to put all custom routes above the Default route.
So this brings up the next question...
how does the "Default" route match (I
assume they use regular expressions
here) the "Page" route?
The Default route matches based on what we call Convention over Configuration. Scott Guthrie explains it well in his first blog post on ASP.NET MVC. I recommend that you read through it and also his other posts. Keep in mind that these were posted based on the first CTP and the framework has changed. You can also find web cast on ASP.NET MVC on the asp.net site by Scott Hanselman.
http://weblogs.asp.net/scottgu/archive/2007/11/13/asp-net-mvc-framework-part-1.aspx
http://www.asp.net/MVC/
I just answered my own question. I had the routes backwards (Default was above page). Below is the correct order. So this brings up the next question... how does the "Default" route match (I assume they use regular expressions here) the "Page" route?
routes.MapRoute(
"Page",
"{Name}.aspx",
new { controller = "Page", action = "Display", id = "" }
);
routes.MapRoute(
"Default", // Route name
"{controller}/{action}/{id}", // URL with parameters
new { controller = "Home", action = "Index", id = "" } // Parameter defaults
);
On one of Rob Conery's MVC Storefront screencasts, he encounters this exact issue. It's at around the 23 minute mark if you're interested.
Not sure how your controller looks, the error seems to be pointing to the fact that it can't find the controller. Did you inherit off of Controller after creating the PageController class? Is the PageController located in the Controllers directory?
Here is my route in the Global.asax.cs
routes.MapRoute(
"Page",
"{Page}.aspx",
new { controller = "Page", action = "Index", id = "" }
);
Here is my controller, which is located in the Controllers folder:
using System.Web.Mvc;
namespace MvcApplication1.Controllers
{
public class PageController : Controller
{
public void Index()
{
Response.Write("Page.aspx content.");
}
}
}
public class AspxRouteConstraint : IRouteConstraint
{
#region IRouteConstraint Members
public bool Match(HttpContextBase httpContext, Route route, string parameterName, RouteValueDictionary values, RouteDirection routeDirection)
{
return values["aspx"].ToString().EndsWith(".aspx");
}
#endregion
}
register the route for all aspx
routes.MapRoute("all",
"{*aspx}",//catch all url
new { Controller = "Page", Action = "index" },
new AspxRouteConstraint() //return true when the url is end with ".aspx"
);
And you can test the routes by MvcRouteVisualizer