I have been asked to work on already existing code for a .NET MVC Application, and am required to add a new page. I have done this, but am having issues.
The application has a common layout defined in _Layout.cshtml page (I need to use the same layout for my new page). The path is present in Viewstart.cshtml page.
This is how an existing page works:
The controller has this code:
public ViewResult Index()
{
TransactionHistoryViewModel model = new TransactionHistoryViewModel();
model.SearchType = "TransactionHistory";
return View(model);
}
When the code is run, immediately after executing the above lines, it goes on to the _ViewStart.cstml file and executes the following:
#{
Layout = "~/Views/Shared/_Layout.cshtml";
}
But when I try to use the same logic for the controller I have created (I have already set up the models):
public ViewResult Index()
{
TransportPlannerViewModel model = new TransportPlannerViewModel();
model.SearchType = "TransportPlanner";
return View(model);
}
the code stops executing after the above block, and does not move on to the _ViewStart file (I figured this out using breakpoints).
I am required by my employers to maintain consistency with the existing code, so I have tried to stick to the original coding style. Could this be an issue with wrong model mapping or setup?
If you have 2x public ViewResult Index() in the same controller, it is not going to work, you will confuse the application about which method signature to choose, because they are identical.
You should have your TransportPlannerViewModel code in a seperate controller. and this should be pointing to a different View Folder associated with that controller.
Ie. If the controller for the first code block is TransactionHistory, then it will be looking for a view under Views\TransactionHistory\Index.cshtml.
By default it uses the pattern Views\ControllerName\ActionName (methodName) to look for the view.
So to get it to work for your other method, if I understand what you are trying to do correctly, you should have a TransportPlanner Controller, then it will look for your view under Views\TransportPlanner\Index.cshtml.
Please clarify if this is not what you are wanting to do.
Related
This question already has answers here:
How to serve html file from another directory as ActionResult
(6 answers)
Closed 5 years ago.
We have a .NET 4.0, MVC 2 project, where the HomeController looks like this:
[HandleError]
public class HomeController : Controller
{
public ActionResult Index()
{
return View("~/client/index.html");
}
}
All is fine.
But, when we start linking to .NET 4.5 and MVC 4, the runtime can't seem to find this index.html! We get this error:
The view '~/client/index.html' or its master was not found or no view
engine supports the searched locations. The following locations were
searched: ~/client/index.html
How could this be! What might we be missing here.
I've never seen MVC using straight html pages. This is a more typical setup:
Controller
[HandleError]
public class HomeController : Controller
{
public ActionResult Index()
{
return View("Index");
}
}
The view would be /views/Home/Index.cshtml. By default MVC wants views to be in the views folder in a folder corresponding to the controller name.
If you want to have the layout broken into a separate file it would typically be in /views/Shared/.
If your HTML page is self-contained you should be able to move it and rename it to index.cshtml and add the following somewhere on the page.
#{
Layout = null;
}
Take care when locating your html page. Placing it inside a view folder where, by the MVC rules, a controller would be expected to do the handling, causes errors in my testing. Here's one way to make it work, though this isn't really coding to MVC pattern:
You can then reference the page:
Notice I've stepped outside the controller/view structure (not recommended for MVC)
To make it fail, which I'm assuming is similar to what is happening for you:
(notice the html is placed in a view where we'd expect a matching controller method to serve it to a caller)...
But...
So if you insist on going this approach perhaps you can set up a content folder outside your MVC controller/view structure and place your html there. But, again, not to beat the subject to death, you could easily convert this to cshtml and serve it up via a simple method in a controller. Just my two cents' worth..
So I want to have a status page that will show a different layout of the equipment depending on who's using it which will be a variable defined in the web.config. Should I be creating a separate controller per view? Some of the background functions should be similar but some will probably be different in the future. Or should I have the same cshtml file and hide html markup depending on who's using it or not?
I was thinking of doing something like:
#if(System.Configuration.ConfigurationManager.AppSettings["IsSuperUser"] == "true")
{
Status
}
else {
Status
}
Or is this a bad idea?
There are several options, it all depends on your needs and preferences.
Your code will work, however you must also double check permission in your controller! For example, your url will be "/SuperUser/Status" and "/User/Status". Now, what's stopping non-super user to type in "/SuperUser/Status" to the address bar?
One important rule, never trust the end users! Assume that they will not do what you intend them to do.
Given all, my preference would be to include a variable in your Model to identify the user level (super vs non super), then use that to determine the layout in your views. Remember, you can also change the layout of the view based on variable/expression.
#Layout = Model.IsSuperUser ? "_SuperLayout.cshtml" : "_RegularLayout.cshtml";
Sounds like a view concern. I would pass the config data through a dependency in the controller and render partials:
#if (Model.IsSuperUser)
{
#Html.Partial("_SuperUser")
}
else
{
#Html.Partial("_User")
}
The controller can then do something like:
public ActionResult Index()
{
var vm = new MyViewModel();
vm.IsSuperUser = _config.GetSuperUser();
return View(vm);
}
I've got a controller named "TafelController.cs" and a view named "Berekenen.cshtml". (the names aren't made up by me.)
the url "http://localhost:5181/tafel/berekenen" somehow doesn't work, even when adding extensions to berekenen like ".cshtml".
Decapitalizing the names of the controller and the view also doesn't work.
The thing is, I get the proper view when I make the Index() method the following.
public ActionResult Index()
{
return View("berekenen");
}
which is weird, because that's what
http://localhost:portnum/tafel/berekenen
is.
when setting that page as the startpage the URL differs a bit.
Then it becomes
http://localhost:5181/Views/tafel/berekenen.cshtml
Does anyone have any idea what might be happening?
http://localhost:portnum/tafel/berekenen is trying to navigate to a method named Berekenen on TafelController. You need to add the following method
public ActionResult Berekenen()
{
return View();
}
I have a C# MVC Razor site. Typically, Controllers load views from the Views folder. However, I have a special circumstance where I need to render a view outside of the Views folder. How do I do that?
Controller will load /Views/Random/Index.cshtml
Can't load /Random/Index.cshtml
/Random/test.aspx loads with no issues, but can't change cshtml files to aspx files, they need to be built regularly.
I have tried return Redirect("/Random/Index.cshtml") in the Controller, and currently have no controller at all.
The weird thing is it works on my Production environment, but not in localhost. In localhost I get:
The type of page you have requested is not served because it has been explicitly forbidden. The extension '.cshtml' may be incorrect. Please review the URL below and make sure that it is spelled correctly.
Requested URL: /Random/Index.cshtml
You can definitely do this. For doing this you need to create one new custom view engine like
public class MyViewEngine : RazorViewEngine
{
private static string[] AdditionalViewLocations = new[]{
"~/Random/{0}.cshtml"
};
public MyViewEngine()
{
base.PartialViewLocationFormats = base.PartialViewLocationFormats.Union(AdditionalViewLocations).ToArray();
base.ViewLocationFormats = base.ViewLocationFormats.Union(AdditionalViewLocations).ToArray();
base.MasterLocationFormats = base.MasterLocationFormats.Union(AdditionalViewLocations).ToArray();
}
}
Then in you global.asax's Application_Start method register this view engine like this-
ViewEngines.Engines.Add(new MyViewEngine ());
If you want your viewengine to take precedence then insert this at 0th position. like this -
ViewEngines.Engines.Insert(0, new MyViewEngine());
return View("~/AnotherFolder/Index.cshtml")` should work for you.
Do not forget to indicate the Layout in your index view:
#{
Layout="~/Views/Shared/Layout.cshtml";
}
I have opened a sample ASP.NET MVC project.
In HomeController I have created a method (action) named MethodA
public ActionResult MethodA()
{
return View();
}
I have right clicked on MethodA and created a new view called MethodA1
Re-did it and created a new view called MethodA2.
How is this magical relationship done? I looked for the config to tell the compiler that views MethodAX are related to action MethodA, but found none.
What view will the controller return when MethodA is called?
The convention is that if you don't specify a view name, the corresponding view will be the name of the action. So:
public ActionResult MethodA()
{
return View();
}
will render ~/Views/ControllerName/MethodA.cshtml.
But you could also specify a view name:
public ActionResult MethodA()
{
return View("FooBar");
}
and now the ~/Views/ControllerName/FooBar.cshtml view will be rendered.
Or you could even specify a fully qualified view name which is not inside the views folder of the current controller:
public ActionResult MethodA()
{
return View("~/Views/Foo/Baz.cshtml");
}
Now obviously all this assumes Razor as view engine. If you are using WebForms, replace .cshtml with .aspx or .ascx (if you are working with partials).
For example if there is no view it will even tell you where and in what order is looking for views:
Remember: ASP.NET MVC is all about convention over configuration.
The MVC framework use convention over configuration. The framework calls the ExecuteResult on the ViewResult object (created by the return View();). The framework by convention then looks in a number of locations to find a view
If you are using areas the framework will look in the following locations for a view.
/Areas//Views/ControllerName/ViewName.aspx
/Areas//Views/ControllerName/ViewName.ascx
/Areas//Views/Shared/ViewName.aspx
/Areas//Views/Shared/ViewName.ascx
/Areas//Views/ControllerName/ViewName.cshtml
/Areas//Views/ControllerName/ViewName.vbhtml
/Areas//Views/Shared/ViewName.cshtml
/Areas//Views/Shared/ViewName.vbhtml
Without areas (or if you are using areas and no view has been found) the framework will look at the following locations
/Views/ControllerName/ViewName.aspx
/Views/ControllerName/ViewName.ascx
/Views/Shared/ViewName.aspx
/Views/Shared/ViewName.ascx
/Views/ControllerName/ViewName.cshtml
/Views/ControllerName/ViewName.vbhtml
/Views/Shared/ViewName.cshtml
/Views/Shared/ViewName.vbhtml
As soon as the Framework tests a location and finds a file, then the search stops,
and the view that has been found is used to render the response to the client.
There are a number of overriden versions of the View method. The most common one is to render a specific view, outside of the framework convention, by calling it by name. For example
return View("~/Views/AnotherIndex.cshtml");
As an interesting footnote, the framework looks for legacy ASP, C# and VB Razor views (aspx, ascx, cshtml and vbhtml) even though you have a specific view engine.
In MVC controller action is not bound to view.
It uses delegate mechanism to pickup the view.
Model Binding(Mapping)
I was looking for the same and I just made a couple of tests and figured out.
It doesn't save anywhere.
To understand how it works; just do these steps:
In your controller, right click, Add View
Then enter a different View Name
and Ctrl F5
you will get Server error in application.
For example if you right click , Add View in following Index action method and type "Index2" in View name, you will get the error.
public class TestController : Controller
{
// GET: Test
public ActionResult Index()
{
return View();
}
}
So basically there is a 1-1 matching between action name and View name. And you cannot add view for the same method so there is no need to save in a config file.
Now change the view file name in Visual Studio from Index2.cshtml to Index.cshtml then Ctrl+F5. You should see it is working.