How can I get the actual "Main-Controller" in a RenderAction?
Example:
MyRoute:
{controller}/{action}
My url my be:
pages/someaction
tours/someaction
...
In my Site.Master I make a RenderAction:
<% Html.RenderAction("Index", "BreadCrumb"); %>
My BreadCrumbController Action looks like this:
public ActionResult Index(string controller)
{
}
The strings controller contains "BreadCrumb" (which is comprehensible because actually I am in BreadCrumbController).
What's the best way to get the "real" controller (e.g. pages or tours).
Parent view/controller context
If you use MVC 2 RC (don't know about previous releases) you can get to parent controller via view's context, where you will find a property called:
ViewContext ParentActionViewContext;
which is parent view's context and also has a reference to its controller that initiated view rendering...
Routing
It seems to me (from your question) that you have requests with an arbitrary number of route segments... In this case you have two options:
Define your route with a greedy parameter where actions in this case will catch all actions in your request URL
{controller}/{*actions}
Create a custom Route class that will handle your custom route requirements and populate RouteData as needed.
the second one requires a bit more work and routing knowledge but it will help you gain some more knowledge about Asp.net MVC routing. I've done it in the past and it was a valuable lesson. And also an elegant way of handling my custom route requirements.
Could you pass it as a parameter to the controller?
--Site.master--
<% Html.RenderAction("Index", "BreadCrumb"
new { controller = ViewData["controller"] }); %>
--BreadCrumbController.cs--
public ActionResult Index(string controller)
{
}
--ToursController.cs--
public ActionResult SomeAction(...)
{
// ....
ViewData["controller"] = "Tours"
// You could parse the Controller type name from:
// this.ControllerContext.Controller.GetType().Name
// ....
}
What do you mean with "real" controller? Your action points to one controller.
Do you mean the previous controller? So: the controller that was used to render your view where your link was created that points to your breadcrumbcontroller?
Unless you add the name of that controller to the link as a parameter, there is no way to get to that.
Related
I am working on an ASP.NET MVC project. I need to be able to map a route such as this:
http://www.mysite.com/Products/Tennis-Shoes
Where the "Action" part of the URL (Tennis-Shoes") could be one of a list of possibilities. I do not want to have to create a separate Action method in my controller for each. I want to map them all to one Action method and I will handle the View that is displayed from there.
I have this working fine by adding a route mapping. However, there are some "Actions" that will need to have a hyphen in them. ASP.NET MVC routing is trying to parse that hyphen before I can send it to my action. I have tried to create my own custom Route Handler, but it's never even called. Once I had a hyphen, all routes are ignored, even my custom one.
Any suggestions? Details about the hyphen situation? Thanks you.
Looking at the URL and reading your description, Tennis-Shoes in your example doesn't sound like it should be an action, but a Route parameter. Let's say we have the following controller
public class ProductsController : Controller
{
public ActionResult Details(string product)
{
// do something interesting based on product...
return View(product);
}
}
The Details action is going to handle any URLs along the lines of
http://www.mysite.com/Products/{product}
using the following route
routes.MapRoute(
null,
"Products/{product}",
new
{
controller = "Products",
action = "Details"
});
You might decide to use a different View based on the product string, but this is just a basic example.
I have a partial view that shows a list of Categories. I'd like to put that partial view on any page, but I'd like to have it to call to the service and get a list of categories by itself without me having to do that in every controller action. Something like webforms in which you can put a code-behind on it.
For eg.
Actions
public ActionResult Index()
{
JobListViewModel model = new JobListViewModel();
model.Categories= jobService.GetCategories();
return View(model);
}
public ActionResult Details(int id)
{
Job job = jobService.GetJob(id);
return View(job);
}
I created a partial that will take the model.Categories model and display a list. As you can see, the Index page will work fine, but I do not want to call it again in the Details page. Is there a way to make my partialview call to the GetCategories() service by itself?
Use Html.RenderAction - that gives the partial view its own controller action.
You should also mark you partial action with the attribute [ChildActionOnly].
DVark,
As noted in the accepted answer, for your scenario, RenderAction is the most appropriate.
I thought I'd link a little article that distils my thinking on the topic (i.e. when to use RenderPartial vs RenderAction):
http://cbertolasio.wordpress.com/2010/09/21/mvc-html-renderaction-vs-html-renderpartial/
hope it helps
[edit] - as an aside. a year or so ago, i got myself into a few scrapes by not appreciating the power of RenderAction, in favour of RenderPartial. as a result, i had littered the shared view space with lots of partialviews in order to access them from a variety of sources. the moral of the story: know your 'territory' before planting your flag.
How can I determine if current action is a ChildAction or routed main action? Should I check the URL and compare to the action's name? That's not so nice, since it's dependent on routing patterns...
Or should I make two actions of the same name, put a ChildActionOnly on one of them and have separate logic (mainly returning View() or PartialView())? How will the overloads be differentiated?
Okay, from an other perspective: How to make it so, that if it's a ChildAction then return a PartialView, otherwise a full View?
You could use the IsChildAction property:
public ActionResult Index()
{
if (ControllerContext.IsChildAction)
{
// The Index action was invoked as child action using
// #Html.Action("index")
}
...
}
I've a problem with Partial View.
I am developing a blog in asp.net mvc and I would make in my masterpage a list of categories, last post, last comments.
I think that the best solution is to use strongly typed partial view, and in each partial view pass the necessary model.
MY problem is that the model in View.. in any view (connected to the masterpage's contentplaceholder) enter in conflict with the models in partial views and I get an error like this:
The model item passed into the dictionary is of type 'System.Collections.Generic.List`1[Blog.Models.Articoli]' but this dictionary requires a model item of type 'System.Collections.Generic.IEnumerable`1[Blog.Models.Categorie]'.
I found on web a dirty solution that consist of to pass togheter the model of any view, some viewdata, one for every model to pass in partial view. But this solution don't respect DRY Principle..because you must repeat this code for each action!
So, my question is: Can I create a model that contain also partial view's model?
If, yes, in that way?
It Exist another solution more simple?
Thanks for help
How about the View Model Pattern?
I've created wrapper classes that are passed to my views rather than whatever object I would normally use
public class MyCreateUserView
{
public User CreatingUser { get; set; }
public MyPartialViewObject Blah { get; set; }
}
In your view write:
public ActionResult CreateUser()
{
MyCreateUserView createUser = new MyCreateUserView()
{
CreatingUser = GetUserFromSomewhere(),
Blah = GetPartialViewObject();
}
return View(createUser);
}
Then your page header looks like so:
<%# Page Language="C#" Inherits="ViewPage<MyCreateUserView>" %>
and when you render your partial write:
<% Html.RenderPartial("../MyPartialViewObject ", Model.Blah); %>
Instead of solving that with the pattern you describe (which is generally a great pattern), I solve that with calls to RenderAction and have it return a partial view. That way the code is in one place as each call to each view does not have to worry about marshalling all the data you need. If you want to see a short discussion on how to use it, I would check Haack's blog here: http://haacked.com/archive/2009/11/18/aspnetmvc2-render-action.aspx. You can also check out the discussion on this other post here on SO: ASP.NET MVC Master Page Data
Is it considered better practice to post back to the same controller that did the rendering and redirecting from original controller if necessary? Or is it just the same if one jumps to different controllers from the view?
I create two overloaded actions in the controller, one to render the input form using an HTTP GET and the other to process the form post using an HTTP POST. Something like this:
public ViewResult Foo()
{
return View();
}
[AcceptVerbs(HttpVerbs.Post)]
public ViewResult Foo( FormCollection form )
{
// process input
if (inputOK)
return RedirectToAction("Index");
return View();
}
The benefit of doing it this way is that if there's an error, the view gets re-rendered with any error and validation messages. If it's successful, there's a redirect to another action, which avoids the duplicate posting warning on browsers if a user refreshes the page - see Post/Redirect/Get on Wikipedia and this blog entry by Stephen Walther.
There are alternatives to taking a FormCollection, e.g. a list of simple parameters or binding to an object. See this article by ScottGu.
I think that the action that is being called should be contained within a relevant controller for that action. If the view needs to call the action it should call it from the relevant controller, not necessarily the controller that it was spawned from.
If you have an inventory controller you don't want to define actions that relate to administration even if an inventory screen might have an administration action on it, as an example.