I've a couple conceptual questions about the relationship between the Controller Action Method and the View:
I see that the name of the view is in function of Controller's name; the name of the controller class is the same of the namespace of the view (represented by the name of the folder where is the .cshtml file) and the name of the method is the same name of the .cshtml file which is the view. Why it works so? If I miss something in the explanation, How it exactly work?
Is there a way where I can put the .cshtml files (views) outside from the folder which match the name of the Controller's class name?
Is a restriction from MVC that names of .cshtml files match the name of the controllers action methods?
What exactly is the View() method which is returned in the controller action method?
Why the methods of the controller class are called "Controller Action Methods"?
Is a restriction from MVC that the names for the controllers end with "Controller" word?
Thanks to all
I would highly suggest running through a tutorial on MVC, such as this codeproject tutorial.
Naming convention are not set in stone, but in general allows for an understandable structure.
Yes, to navigate to a View you can specify the path. return View("~/this/is/your/path/ViewName.cshtml");
No. See above, you can return any view from any methods with the correct path, assuming the return type fits the return type of the method (Explained below).
View() is a C# "method" which tells the project to navigate to the View you specify, along with any parameters you pass. A more correct and in depth answer can be found by looking at the docs. The default return View() attemps to navigate to the return View("MethodName");
Action methods are methods with a return type of ActionResult. Redirect and View are examples of such. Think of them as similar to object return types, such as void or string, but instead ActionResult will tell your project to do something, such as redirect to another method or return a ViewResult via View().
No. Try it! It is however usually good practice, as it will easily separate your files by name, since you will likely have similar filenames n your project.
Related
In an asp.net MVC application, I need to produce some documens, HTML and PDF, which are not sent to the user's browser, but either sent by mail or entered in our document journalizing system. I produce these documents using Razor.
When a document is used only once, I just add a method to the relevant controller, and the view to that controller's view folder. This works. But I have a document that must be produced at two places in the application, implemented in separate controllers. I have made a new controller for this document with its own view folder.
My question is now: how do I call a method on this controller? Searching the web gives many answers, but all redirect the user to this document, which is not what I need.
You can just call it like you would any other method e.g.
public ActionResult DoSomething()
{
// Some code
var otherController = new OtherController(); // The other controller where the method is
otherController.CreatePdf(); // Call the method
// Continue with what ever else you need to do
return View(); // This will then return the `DoSomething` View
}
But personally it doesn't seem like this logic belongs in a controller. You should possibly think about refactoring this logic out of a controller and into a more logical place. Possibly create your own document generation class and use that.
If I'm getting you right.You could create a base controller and add the method there. You can inherit the Base controller in any controller where you want to call the method. here's a link that might help show you the use of Base controllers. How to wire common code from a base controller in ASP.NET MVC.
I have 2 controllers which are SearchController and SearchByStaffController respectively. They are very similar and both have an action with action name "Search". When I call View("Search") in their common super class, the confusion comes. Only the "Search" view with SearchController is rendered.
Does the MVC framework get only the first view that matches the name and ignore the rest?
I tried to pass the view path in View() and it worked. Would there be any side effect for doing so? I searched over the web and seems no one has done this before.
Thanks!
Does the MVC framework get only the first view that matches the name and ignore the rest?
Yes. The routing rules are aparsed (top to bottom) and when a rule is matched all end.
I tried to pass the view path in View() and it worked. Would there be any side effect for doing so? I searched over the web and seems no one has done this before.
You can but I don't like that because MVC is based on conventions. So, I see forcing the path of the view a way to broke a convention. Are you sure you can't simply create two routing rules for the two methods? So you can do something like this:
return RedirectToAction("Search", "Controller1");
and
return RedirectToAction("Search", "Controller2");
user932390,
mvc uses convention over configuration. this means that the 'search' view will have to be located in both the:
views/Search
and
views/SearchByStaff
folders respectively. the only way around this is to locate the search view under the views/shared folder, then the viewengine will find it there in both cases and use it (assuming they have the same model).
Say there's HomeController with an Details-action. return View() will send data to the Detals.aspx in the Home folder. But who makes that binding? and what if I want it to go to Edit.aspx instead?
Background:
Alot of the code in Details.aspx and Edit.aspx is identical, save for one textbox. Maybe by MVC rigor, the view is not supposed to make that kind of decisions, but hey, there's got to be a limit.
You can make it go to Edit.aspx by specifying it as a parameter of the View() function.
return View("Edit");
As to who makes the actual binding happen, it's the View Engine. It receives the returned ViewResult and analyzes it to see which template file to load and display. When it gets the string "Edit", it runs a find routine, using the context of the controller, to search a number of directories for filenames that match the convention. It starts in the controller's View directory, and then searches the Shared directory.
If you want to Edit.aspx to be rendered you could return View("Edit");
This is a basic question about the routing machinery. From a new MVC project, I have this in the HomeController:
public ActionResult MyPage()
{
return View();
}
In the Views\Home folder, I have MyPage.aspx. The routing is still the default of {controller}/{action}/{id}. When I type in http://localhost:1790/Home/MyPage, it is correclty routes to MyPage.aspx. Since I haven't said anything about which view to render, how does ASP.NET MVC know to correctly route to MyPage.aspx? Looks as though the ActionResult name can also be used as the View/aspx page name...unless there is something I misunderstand in how the routing works. I can see how I end up in the Home folder, since the controller name corresponds to the View sub folder name. But does the Action name also correspond to the aspx name?
Would that work if the page was a PHP?
ASP.NET MVC subscribes to what is known as the Convention over Configuration paradigm whereas if you follow their conventions, basic things such as routing concerns will happen for you. But they also allow you to configure them if desired.
MVC implicitly assumes that if you return just View(), that you want View("MyPage") (i.e. the action name). No sense in repeating yourself unnecessarily.
It won't find a PHP file by default, but I'm sure you could override that behavior if you really wanted to. I can't imagine a sane scenario where you would be mixing PHP and ASP.NET MVC, but who knows :)
Action name is the same as the view / partial view name.
asp.net mvc doesn't work with php as far as I'm aware.
As has already been stated, ASP.NET MVC uses convention over configuration. Out of the box, your folder structure is something like this (only showing relevant portions and doing it from memory so...)
Site Root
+ Controllers
HomeController.cs
AccountController.cs
+ Views
+ Home
Index.aspx
+ Account
Index.aspx
+ Shared
The default routing handler is something similar to the following:
"{controller}/{action}/{id}"
There are default values for the route, but if you have a url that is a/b/c, it will look for action a on controller aController and pass it c as a parameter if said method on the controller accepts parameters.
A couple of things about that then need to be clarified. Again, convention over configuration:
1) All controller classes must end with Controller if you're using the default engine. That way, when a request comes in and the {controller} value is parsed, the engine adds Controller to it, looks in the Controller folder (and, thus, namespace), and locates the class.
2) By default -- this can be changed -- all views for a controller must reside in the Views/{controller} folder or in the Views/Shared folder.
3) Public methods on a controller are, by default, actions. You can hide this with an attribute to make themethod unavailable to the engine, but by default they are public.
So, when a request comes in the route is compared against all known routes (global.asax) and the first route that matches the request is accepted. The route is then parsed into the component parts to determine the controller, action, and parameters for the action.
Once the controller is identified, the engine instantiates an instance of that controller and executes the matching method (action) should it be found.
The action will return an ActionResult. View is an extensino method that actually returns ViewResult (if I remember that correctly). The default view for an action is a view of the same name as teh action residing in the Views/{ControllerName} folder.
Routing is a beast unto itself and I'd recommend a good bit of reading on it if you're going to play with it. Minutes to understand but a lifetime to master sorta thing.
To my knowledge, BTW, there is no engine that will use a php page as a view for a controller action.
If I'm not mistaken - the conventions of ASP.NET MVC seem to want me to do the following for a controller view.
Thats to day I create 'Products' directory into which I place my 'Index' view. I then create a 'ProductsController' and create an 'Index' method on it which returns a View. Returning just View() with no arguments will go and fetch the 'Index.aspx' page because its the same name as the method.
public class ProductsController : Controller
{
public ActionResult Index()
{
return View(); // looks for Index.aspx in Products directory
}
}
Now thats just fine. BUT I'll end up with a billion Index.aspx pages, and I'm one of these people that never closes any files so I'll end up going crazy.
Alternatively I can create Products/Products.aspx and change my controller to the following :
public class ProductsController : Controller
{
public ActionResult Index() // my default routing goes to Index (from sample project)
{
return View("Products");
}
}
I understand how that works, and that its completely fine within the MVC design pattern to do this. Its not a hack or anything like that.
My problem (after listening to this PDC video) is that convention over customizabiltity is favored in MVC (or whatever the correct phrase is).
So I'm wondering if I'm missing a third way, or if people are just fine with 50 Index tabs in Visual Studio?
Having the default action for each controller have the same name just simplifies the routing (check global.asax). Also, it all things (Products, Books, Contacts, ...) use actions/views with the same name for the same function, then the code becomes much easier to navigate and understand. This use of convention is especially important when working as part of a team as it will encourage consistent code across developers.
While looking at another question, I ran across SimplyRestfulRouting in the MVCContrib project on codeplex. This might give you some ideas.
I think you should name the method after the action and name the view (if it makes sense and it's not shared between actions, the same as the action). You should probably change your routing mechanism as Index isn't really a descriptive name. The action name should represent what it does (just like any method) and shouldn't be hardcoded to Index or something like that. Routing should be edited instead.
It's just a pattern. Use the pattern, but make it work for you. Personally, I like to have my Views named by their function and I don't have many Index.aspx pages, because I don't have many indices.