Develop Reference

ASP.NET MVC redirect to action Redirect Loops

I am learning asp.net MVC and I was trying Redirect to action and I tried the following code and I keep getting Redirect Loop Error.
This is the Controller class in which I am getting an error
public class CuisineController : Controller
{
// GET: Cuisine
public ActionResult Search(string name)
{
return RedirectToAction("About","Cuisine");
}
public ActionResult Index()
{
return Content("This is Index");
}
public ActionResult About()
{
return Content("this is About");
}
}
I have also created a route of my own other than the Default route
routes.MapRoute(name: "Cuisine",
url: "cuisine/{name}",
defaults: new { controller = "Cuisine", action = "Search", name = UrlParameter.Optional });
When I try to access the Cuisine controller it gives me a redirect loop error.
Thank you

In your routeConfig, you have a route defined for "cuisine/{name}" and it will be sent to the Search action method.
In your Search action method, You are redirecting to the About, Which is cuisine/About. This is matching with the route you defined cuisine/{name} so it will send the request to Search action again. The same process will keep running. That is why you are getting the redirect loop
You should either delete this specific route you defined or rename the url pattern for cusine search to prevent the redirect loop.
routes.MapRoute(name: "Cuisine",
url: "searchcuisine/{name}",
defaults: new { controller = "Cuisine", action = "Search",
name = UrlParameter.Optional });

This should be pretty obvious:
routes.MapRoute(name: "Cuisine",
url: "cuisine/{name}",
defaults: new { controller = "Cuisine", action = "Search", name = UrlParameter.Optional })
Says all urls that start with cuisine/ use the Search method on the CuisineController.
/Cuisine/About starts with that url, so it willl always use the Search method.

It looks like you want to make {name} part of URL. You can use attribute routing instead of changing default routing, it does not have such global "destructive" effects (explained in other answers) at least, and looks it's what you are actually after :)
[Route("Search/{name}")]
public ActionResult Search(string name)
{
return RedirectToAction("About", "Home");
}
See more about attribute routing here (for this to work, don't forget to add routes.MapMvcAttributeRoutes() if it is not there yet).

You need to restore controller action pattern. Just change url: "cuisine/{name}" to url: "cuisine/{action}/{name}"

ASP MCV: Index action with optional string parameter

I would like to have an Index action with an optional string parameter. I'm unable to make it work.
I need the following routes:
http://mysite/download
http://mysite/download/4.1.54.28
The first route will send a null model to the Index view, and the second one will send an string with the version number.
How can I define the route and the controller?
This is my route definition:
routes.MapRoute(
name: "Download",
url: "Download/{version}",
defaults: new { controller = "Download", action = "Index", version = UrlParameter.Optional }
);
routes.MapRoute(
name: "Default",
url: "{controller}/{action}/{id}",
defaults: new { controller = "Home", action = "Index", id = UrlParameter.Optional }
);
And this is the controller:
public ActionResult Index(string version)
{
return View(version);
}
Why does this not work? I'm not an expert in ASP MVC but this seems to be a very simple problem.
The error
When I go to http://mysite/downloads it works fine
When I go to http://mysite/downloads/4.5.6, the controller is correctly called, and the parameter is correctly passed. But then seems that the view is not found. This is the error I found:

string? will not work because string is not a value type.
You can set a default value to your parameter:
public ActionResult Index(string version="")
{
return View(version);
}

The issue is fixed passing the parameter to the view in the following way:
public ActionResult Index(string version)
{
return View((object)version);
}
Or
public ActionResult Index(string version)
{
return View("Index", version);
}
When you pass a string model to the view, if the model is a string parameter, it is interpreted as the view name due to the following overload method
View(String viewName)

Your Download route is conflicting with your Default route. Comment out the Download route and it will probably work.
BTW you can install RouteDebugger to figure out these kind of problems for yourself.

Your controller is looking for a view with the same name as the version attribute entered in the url (e.g. 4.1.54.28). Are you intentionally looking for a view with that name, in which case it should be in the Views/Download folder or your project. If however you simply want to pass it to the default view as a variable to be used on the page your best off sticking it in a model or you can just stick it in ViewBag if it's a one off.
Also you don't need to use:
Public ActionResult Index(string version)
You can use routedata instead e.g.
Public ActionResult Index()
{
string version = RouteData.Values["Version"].ToString();
ViewBag.version = version;
return View();
}
Hope this of some help

You are not set action name in url like {action}
you can try:
routes.MapRoute(
name: "Download",
url: "Download/{action}/{version}",
defaults: new { controller = "Download", action = "Index", version = UrlParameter.Optional }
);

I'm pretty sure it's because in the View you state it is an optional parameter, but your controller says that it is mandatory. Change the signature of your index method to expect a nullable param
public ActionResult Index(string? version)
{
return View(version);
}

Why not have two methods in your download controller:
public ActionResult Index()
{
return View();
}
[HttpGet, ActionName("Index")]
public ActionResult IndexWithVersion(string version)
{
return View(version);
}

How to set up routing so that Index does show?

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

testing ASP.NET MVC controller Httpget

We just started using ASP.NET MVC3 and we want to unit test our controller.
Here is my controller function:
[HttpGet]
Public ActionResult Action()
{
Guid Id = Guid.Empty;
string[] UrlSegments = Request.Url.Segments;
Guid.TryParse(UrlSegments[UrlSegments.Count() - 1], out Id);
if(Id == Guid.Empty)
return RedirectToAction("ErrorPage");
}
I want to test this controller function.I have put the matching route to match this function in my global.asax file. Basically I am trying to retrieve the guid from the URl and if it is not good then take him to error page.
HttpRequestBase class URl is no setter,so I am confused how to test this functionality?

As for testing read the link provided in the comments above but I would recommend doing some reading on MVC Routing or here, it does exactly what you are trying to achieve.
Have a look in your global.ascx.cs file you will find something like this:
routes.IgnoreRoute("{resource}.axd/{*pathInfo}");
routes.MapRoute(
"Default", // Route name
"{controller}/{action}/{id}", // URL with parameters
new { controller = "Home", action = "Index", id = UrlParameter.Optional } // Parameter defaults
);
This is the out of the box route for the MVC framework.
Routes will match a url based on the convention you give them.
So based on the default route above and given a url like this:
http://localhost:portnumber/MyController/MyAction/8B4B93DE-76CA-4552-B4AA-460400761EAD
It will try and match this url to a controller called MyController with an action called MyAction, which receives and Id. It will only hit this action if all the criteria match.
If there is no id in the URL and id defined on your action method is not a nullable type then it simple wont execute. It will rather try match another Url, if it cant find one it will give a 404.
Like this:
public class MyController : Controller {
[HttpGet]
Public ActionResult MyAction(Guid id)
{
}
}

Using the ASP.NET MVC Attribute Based Route Mapper

In my ASP.NET MVC application, I want to use this ASP.NET MVC Attribute Based Route Mapper, first announced here.
So far, I understand how to implement code that uses it, but I've run into a few questions that I think those who have used this attribute-based route mapper in the past will be able to answer.
How do I use it with ActionResults that are for HTTP POSTs? In other words, how does it work with form submissions and the like? Should I just put the URL of the GET method in, or should I use the GET method URL without any parameters (as in HTTP POST they aren't passed in through the URL)?
How do I use it with "URL querystring parameters"? Can the attribute be configured to map to a route such as /controller/action?id=value rather than /controller/action/{id}?
Thanks in advance.

How do I use it with ActionResults
that are for HTTP POSTs?
You decorate the action that you are posting to with the [HttpPost] attribute:
[Url("")]
public ActionResult Index() { return View(); }
[Url("")]
[HttpPost]
public ActionResult Index(string id) { return View(); }
If you decide to give the POST action a different name:
[Url("")]
public ActionResult Index() { return View(); }
[Url("foo")]
[HttpPost]
public ActionResult Index(string id) { return View(); }
You need to supply this name in your helper methods:
<% using (Html.BeginForm("foo", "home", new { id = "123" })) { %>
How do I use it with "URL querystring
parameters"?
Query string parameters are not part of the route definition. You can always obtain them in a controller action either as action parameter or from Request.Params.
As far as the id parameter is concerned it is configured in Application_Start, so if you want it to appear in the query string instead of being part of the route simply remove it from this route definition:
public static void RegisterRoutes(RouteCollection routes)
{
routes.IgnoreRoute("{resource}.axd/{*pathInfo}");
routes.MapRoutes();
routes.MapRoute(
"Default",
"{controller}/{action}",
new { controller = "Home", action = "Index" }
);
}