Develop Reference

Why does an ASP.NET MVC route have a name?

In an ASP.NET MVC 5 web application, there is a RouteConfig class that registers many routes. In all of the examples I have seen so far, only the "Default" route has a non-empty name. The URL pattern and default route values seem to be sufficient to correctly associate any URL to the controller and action to execute. So, is there any benefit to naming a route? For debugging or logging? Just for self-documenting the code?
For example:
public class RouteConfig
{
public static void RegisterRoutes( RouteCollection routes )
{
routes.IgnoreRoute( "{resource}.axd/{*pathInfo}" );
// Most pages.
routes.MapRoute( name: "Default",
url: "{controller}/{action}/{id}",
defaults: new { controller = "home", action = "index", id = UrlParameter.Optional }
// A special page.
// Should the route have a name?
routes.MapRoute( name: "",
url: "special",
defaults: new { controller = "special", action = "index", HttpVerbs = HttpVerbs.Get } );
}
}

The main reason to name a route is so that if you need a link to a route from somewhere in the app, you can reference the name. That way if the actual URL/path changes you don't break everywhere in the code that references that route.

ASP.NET MVC routing add special convention mysitye/string

I am new to ASP.NET MVC. I have a web page with default routing:
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 }
);
}
I have been working on developing an URL shortener that creates 5 character strings in base 32 (A-Z 0-9). My idea is to have the default routing in ASP.NET MVC and add a special case for
// this is the random code generated by my application
www.mypage.com/ASD12
How can I add this exception to my routing and always make URLs (mypage.test/code) land on a specific controller action?
public class CodeController : Controller
{
public async Task<ActionResult> Index(string code)
{
//do things here
}
}
Thank you very much

After searching more,
routes.MapRoute(
name: "specialConvention",
url: "{id}",
defaults: new { controller = "code", action = "Index" }
);
That is the code I was looking for.

Implementing Attribute Routing

I'm trying to get a handle on attribute routing in MVC.
Initially, the routing for my sitemap controller was as follows:
public class RouteConfig
{
public static void RegisterRoutes(RouteCollection routes)
{
routes.IgnoreRoute("{resource}.axd/{*pathInfo}");
routes.MapRoute(
name: "SitemapXml",
url: "sitemap.xml",
defaults: new { controller = "Sitemap", action = "Index" }
// Additional mappings...
}
}
That works fine. But then I tried commenting out the SitemapXml routing above and instead adding an attribute in my controller.
// GET: Sitemap
[Route("sitemap.xml")]
public ActionResult Index()
{
// Generate sitemap
}
I also added the following line at the end of RegisterRoutes:
routes.MapMvcAttributeRoutes();
But now when I navigate to domain.com/sitemap.xml, I get a page not found error.
Questions:
What steps am I missing to get my routing attribute to work?
Since mappings can now be specified in two places (as attributes or set directly in the RouteCollection), what happens when those two places contradict each other?

if you remove the extension .xml , your attribute routing will work perfectly. And its better to use the extension related code in action method.
Also make sure your route config looke like (routes.MapMvcAttributeRoutes(); should exist before default route)
routes.MapMvcAttributeRoutes();
routes.MapRoute(
name: "Default",
url: "{controller}/{action}/{id}",
defaults: new { controller = "Account", action = "Login", id = UrlParameter.Optional }
);

ASP.NET Passing Parameter in URL

I wrote a very simple web app in Flask and am porting it to ASP.NET Framework. All the functionality is in JavaScript and HTMl, so the framework should just act as scaffolding. I've got almost everything ported over, except for what seems to be a routing issue. My site expects a string token variable to be appended to the URL, like so: www.mysite.com/token-string. For development, the URL is localhost:*****/string-token, with my Index.cshtml page being displayed as default.
When I pass the URL without the token it works fine and my index page loads. However I get a 404 when I try it with the token. I'm assuming it's identifying the token as a route and is trying to navigate to it? I'm not sure how to fix it. Here are the important parts of my code:
HomeController.cs:
public class HomeController : Controller
{
public ActionResult Index(string token)
{
return View();
}
}
RouteConfig.cs:
NB: I've not changed this, not sure what to do with it.
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 }
);
}
}
It's quite important that the token is passed in the way it is, rather than as a ? query parameter or anything like that. Additionally, the C# index view doesn't really need to do anything with the token - it gets extracted by the JavaScript.
Any advice is most welcome. Thanks.

Each segment (i.e. {controller}) in the route is a variable, and in the default route makes them all optional. Therefore, your default route is matching the request www.mysite.com/token-string.
What you need to do is insert a route that has a constraint to only match URLs with your token. Assuming your token is a GUID, you could use a regex route constraint as follows:
public class RouteConfig
{
public static void RegisterRoutes(RouteCollection routes)
{
routes.IgnoreRoute("{resource}.axd/{*pathInfo}");
routes.MapRoute(
name: "TokenRoute",
url: "{token}",
defaults: new { controller = "Home", action = "Index" },
constraints: new { token = #"^[0-9A-Fa-f]{8}[-][0-9A-Fa-f]{4}[-][0-9A-Fa-f]{4}[-][0-9A-Fa-f]{4}[-][0-9A-Fa-f]{12}$" }
);
routes.MapRoute(
name: "Default",
url: "{controller}/{action}/{id}",
defaults: new { controller = "Home", action = "Index", id = UrlParameter.Optional }
);
}
}
If your token is not a GUID, you could either use a different regex or implement IRouteConstraint to ensure the route only matches your tokens. The logic you use could be as simple as a == statement (as shown) or more complex (such as a database lookup).
public static void RegisterRoutes(RouteCollection routes)
{
routes.IgnoreRoute("{resource}.axd/{*pathInfo}");
routes.MapRoute(
name: "TokenRoute",
url: "{token}",
defaults: new { controller = "Home", action = "Index" },
constraints: new { token = new TokenConstraint() }
);
routes.MapRoute(
name: "Default",
url: "{controller}/{action}/{id}",
defaults: new { controller = "Home", action = "Index", id = UrlParameter.Optional }
);
}
public class TokenConstraint : IRouteConstraint
{
public bool Match(HttpContextBase httpContext, Route route, string parameterName, RouteValueDictionary values, RouteDirection routeDirection)
{
if ((string)values[parameterName] == "MyToken")
{
return true;
}
return false;
}
}
Note that you should use the route value key {token} in the url: parameter to match the action method parameter name token.
public ActionResult Index(string token)
{
return View();
}

I guess you could try changing the default route to include token instead of id as shown below.
routes.MapRoute(
name: "Default",
url: "{controller}/{action}/{token}",
defaults: new { controller = "Home", action = "Index", id = UrlParameter.Optional }
);

The default Route pattern which you have expects the parameter with name as 'id'
Either add (or modify the default route) like below route pattern
routes.MapRoute(
name: "AnotherRoute", //your desired route name
url: "{controller}/{action}/{token-string}",
defaults: new { controller = "Home", action = "Index", id = UrlParameter.Optional }
);

Map Custom Route ASP.NET MVC5

I haven't used .NET Routing before.
I have a URL: http://myurl.com/Account/Login/?IsIPA=true.
I want to be able to hit this URL with the following: http://myurl.com/IPA
This is the only custom route I want hit.
Can I create a route just for a single URL like this?
My code that isn't working is:
public static void RegisterRoutes(RouteCollection routes)
{
routes.IgnoreRoute("{resource}.axd/{*pathInfo}");
routes.MapMvcAttributeRoutes();
routes.MapRoute(
name: "Default",
url: "{controller}/{action}/{id}",
defaults: new { controller = "Home", action = "Index", id = UrlParameter.Optional }
);
routes.MapRoute("IPA", "Account/Login/{IsIPA}", new { controller = "Account", action = "Login", IsIPA = "true" });
}
I get the error:
The constraint entry IsIPA on the route with route template Account/Login/{IsIPA}=True must have a string value or be of a type which implements System.Web.Routing.IRouteConstraint.

Route matching is similar to a switch case statement. The url parameter and any default values and constraints are all considered to determine whether or not it is a match with the incoming URL. If the route matches, it will then create a dictionary of route values based on the configuration. If the route does not match, the next route in the collection is tried until a match is found (or not).
This means the order that routes are specified is important. The default route matches any URL with 0, 1, 2, or 3 segments. Therefore, in most cases you will need to define your custom route before the default route.
public static void RegisterRoutes(RouteCollection routes)
{
routes.IgnoreRoute("{resource}.axd/{*pathInfo}");
routes.MapMvcAttributeRoutes();
routes.MapRoute(
name: "IPA",
url: "IPA",
defaults: new { controller = "Account", action = "Login", IsIPA = "true" });
routes.MapRoute(
name: "Default",
url: "{controller}/{action}/{id}",
defaults: new { controller = "Home", action = "Index", id = UrlParameter.Optional }
);
}
The above configuration will route http://myurl.com/IPA to the Controller named Account and Action method named Login, and pass the additional route key IsIPA. This same URL will be built for the Controller/Action/IsIPA combination because it is the first one that matches in the list.
Note that the original URL http://myurl.com/Account/Login/?IsIPA=true will still work and still route to the same location. This configuration just adds an extra route to that resource.

Without testing it, I think that you want this:
routes.MapRoute("IPA", "Account/Login/{IsIPA}",
new { controller = "Account", action = "Login", IsIPA = "true"});