Weird behavior of urlrewriting in MVC3 with razor viewengine - asp.net-mvc-3

I am working on a project which adopted ASP.NET MVC3(Razor) tech.
Now, I have a controller below:
public class Home: Controller
{
public ActionResult Result(string id)
{
return View(id);
}
}
and I have set MapRoute as below:
context.MapRoute(
"Home_result",
"Home/Result/{id}",
new { controller="Home", action = "Result"}
);
and it was suposed to display a View which named "Result" when I typed the url http://domain.com/Home/Result/abc123 in the browser. However it didn't.
Instead it gave me an exception below:
The view 'Result' or its master was not found or no view engine supports the searched locations. The following locations were searched:
~/Views/Home/abc123.cshtml
~/Views/Home/abc123.vbhtml
~/Views/Shared/abc123.cshtml
~/Views/Shared/abc123.vbhtml
It is strange isn't it?
Can anyone help me to figure out what mistakes I've made?

return View(id);
Returns a view with the name of ID's value (.cshtml), not the view with the name result.cshtml. I think this is because Id is a string. Are you trying to pass the id to the view?
To return the view matching the name of your controller's action simply use
return View();
If you want to pass that value to the view, for what ever crazy reason, using the viewbag is the easiest way since the string id is being used to declare a view name.
ViewBag.ID = id;
return View();
Then in the view just use the value you stored. And yes Razor HTML encodes by default.
#ViewBag.ID

Related

.Net Core View Components won't work without custom View Model

I have a MVC.Net Core 2.0 application (it was originally 1.1 before I upgraded it) that has an odd quirk to it. In order to call a View Component from my page, I have to create a custom View Model. If I use a built in type, like string, the routing handler fails to find it.
Example:
I created a pretty simple ViewComponent that I am trying to call from my View, that only need a single string. But if I created with InvokeAsync(string) instead of InvokeAsync(customVm) I get an error suggesting the routing is trying to use the string parameter as part of the path.
ViewComponent:
public class SkilledQaPreviousComments : ViewComponent
{
public async Task<IViewComponentResult> InvokeAsync(string vm)
{
return View(vm);
}
}
Calling View:
#await Component.InvokeAsync(nameof(SkilledQaPreviousComments), new { vm = Model.QaReviewEditReasonPrevious })
Startup.cs:
app.UseMvc(routes =>
{
routes.MapRoute(name: "areaRoute", template: "{area:exists}/{controller=Home}/{action=Index}/{id?}");
routes.MapRoute(name: "default", template: "{controller=Home}/{action=Index}/{id?}");
});
File locations:
Error Message given Model.QaReviewEditReasonPrevious = "[\"single\"]":
The view 'Components/SkilledQaPreviousComments/["test"]' was not found. The following locations were searched:
/Areas/NurseForms/Views/Signature/Components/SkilledQaPreviousComments/["test"].cshtml
/Areas/NurseForms/Views/Shared/Components/SkilledQaPreviousComments/["test"].cshtml
/Views/Shared/Components/SkilledQaPreviousComments/["test"].cshtml
If I change the view component to accept an int and pass 1 I get the same error just with '1' instead of '["test"]'.
I just can't figure out why it's not looking for Default.cshtml. Other view components in the project are working, but everyone of them has a custom view model. I'd rather not create a custom view model just to hold a string every time but right now that's my only option.
Ideas/Obvious things I've done wrong here?
For this issue, it is caused by the missmatch View method you want to return.
Check the ViewComponent source code, it defines below methods to return View:
public ViewViewComponentResult View<TModel>(string viewName, TModel model);
public ViewViewComponentResult View<TModel>(TModel model);
public ViewViewComponentResult View(string viewName);
public ViewViewComponentResult View();
When you return return View(vm); which vm is a string, it will match to View(string viewName); for best match, and it will look for the specific viewName instead of return the Default view and model.
You could try code below to use View<TModel>(TModel model);.
public async Task<IViewComponentResult> InvokeAsync(string vm)
{
return View<string>(vm);
}

ASP.NET MVC 3 won't recognise .cshtml view files

I have ported an mvc 3 app from vs 2010 to vs2012.
The ported app is using .NET 4.
All the old bits work, but with a new view, created in vs 2012, the view engine is not looking for .cshtml files for the view.
For example, when the user requests the index action on the Welcome controller in the Solicitors area, the url is:
mysite.com/solicitors/welcome/gg
(where gg is the user name). In that case, the error that comes back is:
The view 'Index' or its master was not found or no view engine
supports the searched locations. The following locations were
searched: ~/Areas/Solicitors/Views/Welcome/Index.aspx
~/Areas/Solicitors/Views/Welcome/Index.ascx
~/Areas/Solicitors/Views/Shared/Index.aspx
~/Areas/Solicitors/Views/Shared/Index.ascx ~/Views/Welcome/Index.aspx
~/Views/Welcome/Index.ascx ~/Views/Shared/Index.aspx
~/Views/Shared/Index.ascx ~/Areas/Solicitors/Views/Welcome/gg.master
~/Areas/Solicitors/Views/Shared/gg.master ~/Views/Welcome/gg.master
~/Views/Shared/gg.master ~/Areas/Solicitors/Views/Welcome/gg.cshtml
~/Areas/Solicitors/Views/Welcome/gg.vbhtml
~/Areas/Solicitors/Views/Shared/gg.cshtml
~/Areas/Solicitors/Views/Shared/gg.vbhtml ~/Views/Welcome/gg.cshtml
~/Views/Welcome/gg.vbhtml ~/Views/Shared/gg.cshtml
~/Views/Shared/gg.vbhtml
I have already added the following key to appsettings in web.config, but it makes no difference.
<add key="webpages:Version" value="1.0" />
EDIT:
Route in SolictorAreaRegistration.cs:
context.MapRoute(
"Solicitors_Welcome",
"Solicitors/Welcome/{nameUser}",
new { controller = "Welcome", action = "Index", nameUser = UrlParameter.Optional }
);
EDIT 2:
Using RouteDebug, I can see that the correct controller and action are found.
Route Data
Key Value
nameUser: gg
controller: Welcome
action: Index
Data Tokens
Key Value
Namespaces: System.String[]
area: Solicitors
UseNamespaceFallback: False
EDIT 3:
The route is found correctly, as I can see from debugging: the Index action is hit.
The problem happens when the line call the view is called:
namespace MyApp.Areas.Solicitors.Controllers
{
[Authorize]
public partial class WelcomeController : Controller
{
//
// GET: /Solicitors/Welcome/
public virtual ActionResult Index(string nameUser)
{
return View("Index", nameUser);
}
}
}
OK, got to the bottom of it:
The Problem:
The problem is that the model of my view is of type string. In my action, I was passing in a string as the model parameter:
public virtual ActionResult Index(string nameUser)
{
return View("Index", nameUser);
}
This will clash with one of the overloads of Controller.View(...):
View(string, string)
The second parameter expects the name of a layout file. When you do this, MVC goes off looking for a layout file with a name of the value of your string, which could be, for example:
"Hello, World. I'm an idiot, but if you give me a decent error message, I might be able to fix the bug."
Obviously, a layout file with that name doesn't exist. Nor does a layout file called "gg" either (my (test) solicitor's username).
The Solution:
The solution is simple:
Specify that the second parameter is the model, not the layout.
public virtual ActionResult Index(string nameUser)
{
return View("Index", model: nameUser);
}
Useful Article:
To view an extended discussion of this very issue, see the following article:
MVC Gotcha: Beware when using your view's model is a string
Many thanks to heartysoft.com for the enlightenment.
It is looking as you can see from the error message:
~/Areas/Solicitors/Views/Welcome/gg.cshtml
If you need to look for the Index view then you need to specify it:
http://mysite.com/solicitors/welcome/index/gg

C# MVC RedirectToAction not working?

So I want to create a new view in my MVC application that allows a user to enter parameters for searching. I want to pass these parameters to another View/Controller and I want the controller to call an action called "Search" to handle these parameters and return the correct data. However, when I try to "Redirect" it is giving me a problem. It says the resource cannot be found,
The view 'Search' or its master was not found or no view engine supports the searched locations.
The following locations were searched:
~/Views/Question/Search.aspx
This is the code.
[HttpPost]
public ActionResult HandleForm()
{
SearchQuery search = new SearchQuery();
if(Request["QuestionID"].Trim()!="")
search.QuestionID = Convert.ToInt32(Request["QuestionID"].Trim());
return RedirectToAction("Search", "Question");
}
However, if I change "Search" to "Index" it loads the page I desire because it opens the view within that page. It does not call the search action. Why is this method returning the View when every example I've read states that the name of the Action needs to be passed?
For those who are wondering this is my global.asax routing info
routes.MapRoute(
"Default", // Route name
"{controller}/{action}/{id}", // URL with parameters
new { controller = "Home", action = "Index", id = UrlParameter.Optional }
Last but not least, I have yet to look into how to pass these parameters, but I hope it won't be too much extra work once I can figure out why this is not working as desired.
Go to the Views/Questions directory and make sure there is a file called Search.cshtml. If it does exist also then make sure that this view has a corresponding action method, something like:
public class QuestionController : Controller
{
public ActionResult Search()
{
}
}
If you are in same controller then write:
return RedirectToAction("Search");
or if your search action is in other controller then write:
return RedirectToAction("Search","your Controller Name Here");

View and controller in asp.net mvc3 - controller should match a view one to one?

I have a very typical situation in any application, where i have the following functionality:
create new record
edit existing record
so other irrelevant actions
IMO, creating and editing should be served by the same view, but different actions. But it appears that I have to have the action name match the view name....would you use partial views for this? I would rather not complicate this scenario - which is very simple and appears in virtually every web app.
Action can return a view with a diferent name this way:
public ActionResult OneName()
{
return View("OtherName");
}
If you don't specify the view name (View("") then the view will be the view with the action name
Partial views are an excellent answer. I'd suggest you look at how the MvcScaffold NuGet package does it. See here or get the package in Visual Studio.
I'd simply use the same action altogether and use the ID to determine if this is a new record or updating an existing one:
/Forum/Post/Edit/0 create a new record
/Forum/Post/Edit/10457 update a record with ID 10457
However, since you insist on using different actions, why not simply create 2 actions, both returning the same view?
public class PostController : Controller
{
public ActionResult Create(Post post)
{
// work your magic...
return View("Edit", post);
}
public ActionResult Update(Post post)
{
// work your magic...
return View("Edit", post);
}
}
If this doesn't work in your scenario, you're pretty much left with partial views.

MVC3 Routing Issues - How to re-use a View for all Controller Methods?

I'm trying to implement a common controller in MVC3 to return various JSON feeds, example -
public class AjaxController : Controller
{
public ActionResult Feed1()
{
ViewBag.Json = LogicFacade.GetFeed1Json();
return View();
}
public ActionResult Feed2()
{
ViewBag.Json = LogicFacade.GetFeed2Json();
return View();
}
}
This class has 30+ methods in it, the problem is this requires implementing an IDENTICAL View for each of the Controller's methods (sigh) that writes out ViewBag.Json.
I'm assuming this is a routing issue but I'm struggling with that. The following didn't work -
Tried setting ViewBag.Json then using RedirectToAction() but that seems to reset ViewBag.Json.
Note JsonResult is not appropriate for my needs, I'm using a different JSON serialiser.
So the objective here is to maintain one View file but keep this class with seperate methods that are called by routing, and not a crappy switch statement implementation.
Any help appreciated.
Use the same view and just specify the name. You can store in the controller's view folder, if only used by one controller, or in the Shared view folder if used by more than one.
return View("SharedJsonView");
Another, perhaps better, solution would be to create your own result -- maybe deriving from JsonResult, maybe directly from ActionResult -- that creates the JSON response that you need. Look at the source code for JsonResult on http://www.codeplex.com/aspnet for ideas on how to do it.

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