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.
Related
I'm developing an MVC3 application with EF and I wanted to make the UI fluent using jQuery ajax, the user will be able to navigate through the url, if he knows it or maybe he might receive a link pointing to a particular route, but, once the page is fully loaded it needs to be fluent, so I came up with one idea and I would like to discuss it here before I make the changes to the solution.
Here is what I came up with:
TestController.cs (Methods code has been omitted for simplicity)
public ActionResult Index() { ... }
public ActionResult Create() { ... }
[HttpPost]
public ActionResult Create(Test test) { ... }
public ActionResult Update(int testID) { ... }
[HttpPost]
public ActionResult Update(Test test) { ... }
public ActionResult Delete(int testID) { ... }
[HttpPost]
public ActionResult Delete(Test test) { ... }
So far it looks like most controllers. My views are as follows:
Views\Test\List.cshtml
Views\Test\Create.cshtml
Views\Test\Details.cshtml
Views\Test\Delete.cshtml
Now since I wanted to do it async: I've changed my List view so I could add, modify and remove from the list, so far is working like a charm. Plus, the user could still be able to navigate through the application using the url's, note that every link inside the application will perform an ajax request to do the actual work, there are no Route/Action links.
By now the application is working as expected, but now I came across something: there are views that I need to be ActionResult and PartialViewResult, that is because the user could type in the url: "/Admin/Test", which should return the full page, or could click on an anchor which will load only the content of the "/Admin/Test" and display it. To avoid the famous page inside page errors I wrote a function to send the request, and when the request arrives it selects only what I need, avoiding then the page inside page, and to duplicate views, but, the response is the whole page which, I don't need to say, it's not the best option, but since the application will be used by lan I didn't care too much about the payload of the response, but then I needed to write javascript code inside the views, so my solution was like null because using the jQuery selector to get only what I need the javascript wasn't there.
As for my new solution to solve my last solution:
I thought I might leave the original view as is, and create another view appending the word "Partial" after the original name, creating another method in the controller with the same naming convention, plus adding the new Route to my Route Table.
To wrap things up, what I need is the following:
- If the user types in "/Test" the response should be the entire page, loaded like the old days, screens flashing white and such.
- But if the user clicks the Test link in the navigation bar, the response should be async and refreshing only the content of my layout.
Any ideas? thoughts? suggestions?
In your actionmethod you can have
if (Request.IsAjaxRequest())
return PartialView("_somePartialView");
else
return PartialView("_someOtherPartialView");
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.
Hey guys,
What is the best mechansims for persisting viewmodel data from one controller to another.
For instance
return RedirectToAction("SomeAction", "SomeController");
I need to have some data from the previous controller available to the new controller I am redirecting to.
If you are not passing an object or something complex, make use of parameters. Just make sure redirected action gets parameters to display what it should.
return RedirectToAction("SomeAction", "SomeController",new { id=someString} );
Get the parameter in the action:
public ActionResult SomeAction(string id)
{
//do something with it
}
#Ufuk Hacıoğulları: You can't share information between 2 controllers using ViewData. ViewData only shares information between Controller and View.
If you need to share complex information between multiple Controllers while redirection, use "TempData" instead.
Here is how you use "TempData" - http://msdn.microsoft.com/en-us/library/dd394711.aspx
A redirect is going to send an http response to the client that directs it to then make a new http request to /SomeController/SomeAction. An alternative would be for you to call a method on your other controller directly... new SomeController().SomeAction(someData) for example.
I think this will be helpfull to you to pass value from one action to another action .
public ActionResult ActionName(string ToUserId)
{
ViewBag.ToUserId = ToUserId;
return View();
}
public ActionResult ssss(string ToUserId)
{
return RedirectToAction("ActionName", "ControllerName", new { id = #ToUserId });
}
We have an a PHP application that we are converting to MVC. The goal is to have the application remain identical in terms of URLs and HTML (SEO and the like + PHP site is still being worked on). We have a booking process made of 3 views and in the current PHP site, all these view post back to the same URL, sending a hidden field to differentiate which page/step in the booking process is being sent back (data between pages is stored in state as the query is built up).
To replicate this in MVC, we could have a single action method that all 3 pages post to, with a single binder that only populates a portion of the model depending on which page it was posted from, and the controller looks at the model and decides what stage is next in the booking process. Or if this is possible (and this is my question), set up a route that can read the POST parameters and based on the values of the POST parameters, route to a differen action method.
As far as i understand there is no support for this in MVC routing as it stands (but i would love to be wrong on this), so where would i need to look at extending MVC in order to support this? (i think multiple action methods is cleaner somehow).
Your help would be much appreciated.
I have come upon two solutions, one devised by someone I work with and then another more elegant solution by me!
The first solution was to specify a class that extends MVcRouteHandler for the specified route. This route handler could examine the route in Form of the HttpContext, read the Form data and then update the RouteData in the RequestContext.
MapRoute(routes,
"Book",
"{locale}/book",
new { controller = "Reservation", action = "Index" }).RouteHandler = new ReservationRouteHandler();
The ReservationRouteHandler looks like this:
public class ReservationRouteHandler: MvcRouteHandler
{
protected override IHttpHandler GetHttpHandler(RequestContext requestContext)
{
var request = requestContext.HttpContext.Request;
// First attempt to match one of the posted tab types
var action = ReservationNavigationHandler.GetActionFromPostData(request);
requestContext.RouteData.Values["action"] = action.ActionName;
requestContext.RouteData.Values["viewStage"] = action.ViewStage;
return base.GetHttpHandler(requestContext);
}
The NavigationHandler actually does the job of looking in the form data but you get the idea.
This solution works, however, it feels a bit clunky and from looking at the controller class you would never know this was happening and wouldn't realise why en-gb/book would point to different methods, not to mention that this doesn't really feel that reusable.
A better solution is to have overloaded methods on the controller i.e. they are all called book in this case and then define your own custome ActionMethodSelectorAttribute. This is what the HttpPost Attribute derives from.
public class FormPostFilterAttribute : ActionMethodSelectorAttribute
{
private readonly string _elementId;
private readonly string _requiredValue;
public FormPostFilterAttribute(string elementId, string requiredValue)
{
_elementId = elementId;
_requiredValue = requiredValue;
}
public override bool IsValidForRequest(ControllerContext controllerContext, System.Reflection.MethodInfo methodInfo)
{
if (string.IsNullOrEmpty(controllerContext.HttpContext.Request.Form[_elementId]))
{
return false;
}
if (controllerContext.HttpContext.Request.Form[_elementId] != _requiredValue)
{
return false;
}
return true;
}
}
MVC calls this class when it tries to resolve the correct action method on a controller given a URL. We then declare the action methods as follows:
public ActionResult Book(HotelSummaryPostData hotelSummary)
{
return View("CustomerDetails");
}
[FormFieldFilter("stepID", "1")]
public ActionResult Book(YourDetailsPostData yourDetails, RequestedViewPostData requestedView)
{
return View(requestedView.RequestedView);
}
[FormFieldFilter("stepID", "2")]
public ActionResult Book(RoomDetailsPostData roomDetails, RequestedViewPostData requestedView)
{
return View(requestedView.RequestedView);
}
[HttpGet]
public ActionResult Book()
{
return View();
}
We have to define the hidden field stepID on the different pages so that when the forms on these pages post back to the common URL the SelectorAttributes correctly determines which action method to invoke. I was suprised that it correctly selects an action method when an identically named method exists with not attribute set, but also glad.
I haven't looked into whether you can stack these method selectors, i imagine that you can though which would make this a pretty damn cool feature in MVC.
I hope this answer is of some use to somebody other than me. :)
I'm using the MVC PHP framework Codeigniter and I have a straight forward question about where to call redirect() from: Controller or Model?
Scenario:
A user navigates to www.example.com/item/555. In my Model I search the item database for an item with the ID of 555. If I find the item, I'll return the result to my controller. However, if an item is not found, I want to redirect the user somewhere. Should this call to redirect() come from inside the model or the controller? Why?
No your model should return false and you should check in your controller like so:
class SampleModel extends Model
{
//Construct
public function FetchItem($id)
{
$result = $this->db->select("*")->from("table")->where("item_id",$id)->get();
if($result->num_rows() == 0)
{
return false;
}
//return result
}
}
and within your controller do:
function item($id)
{
$Item = $this->SampleModel->FetchItem($id);
if(!$Item)
{
redirect("class/error/no_item");
}
}
Models are for data only either return a standard result such as an key/value object or a boolean.
all logic should be handled / controlled by the Controller.
Models are not page specific, and are used globally throughout the whole application, so if another class / method uses the model, it might get redirect to the incorrect location as its a different part of your site.
It seems like the controller would be the best place to invoke your redirect because the controller typically delegates calls to the model, view, or in your case, another controller.
However, you should use whatever makes the most sense for your application and for what will be easier to maintain in the future, but also consider that rules do exist for a reason.
In short, if a coworker were to try to fix a bug in your code, what would the "reasonable person" standard say? Where would most of them be most likely to look for your redirect?
Plus, you said you're returning the result to your controller already... perhaps that's where you should make your redirect...