I have something similar to the following method:
public ActionResult Details(int id)
{
var viewData = new DetailsViewData
{
Booth = BoothRepository.Find(id),
Category = ItemType.HotBuy
};
return View(viewData);
}
and the following Route:
routes.MapRoute("shows","shows/{controller}/{action}/{id}", new {id = 0});
Everything worked fine before the Beta, when I had Preview 3. Now the method will fill the id correctly the first time I execute the action. However the second time the controller's ModelState contains the last-use id value. This causes the ActionInvoker to use it in the method's parameter instead of the Route value.
So if I call the action twice on two different entities the results are such:
www.mysite.com/shows/Booth/Details/1 => Details(1)
www.mysite.com/shows/Booth/Details/2 => Details(1) //from ModelState["id"]
From my quick scan with Reflector it seems it first binds parameters to the ModelState then to Routes. However, I never even posted anything from the model. As far as I can tell the ModelState should not contain anything.
Is this a bug in the Beta, possibly a bug somewhere in my code, or is there some design feature that I am ignorant of? Any insight into the nature of ModelState and why this happens is appreciated.
EDIT:
I discovered that this issue is actually a symptom of what appears to be a bug with the DefaultValueProvider if you instantiate a Controller from an IoC container that exists for the lifetime of the Asp.Net application.What happens is that the DefaultValueProvider uses the first ControllerContext given to the Controller and never updates it until the controller is recreated. This causes old RouteData to be used for method parameters instead of the current RouteData.
It's hard for me to tell what you expect to happen and what is happening from your post. Is it possible there's an error in your BoothRepository.Find method such that it returns the same thing every time?
ModelBinder should not be affecting this method because the parameter to the action method is a simple type, int.
Were both of these requests GET requests? If you still are having problems, can you try and create the simplest repro possible and email it to philha - microsoft dot com?
EDIT: The problem ended up being that the developer was attempting to re-use the valueprovider across requests (by having Castle Windsor manage the lifecycle of Controllers). Right now, there's no support for re-using controller instances across requests like you would with IHttpHandler which has a IsReusable property. So in general, reusing controllers across requests requires doing a lot more work on your end. :)
The problem is the LifeStyle, I completetly overlooked the fact it was being defined, which means by default the controllers will use the Singleton lifestyle. Setting the LifeStyle to Transient for all controllers will sort this problem.
if you use spring.net modify
Controller's singleton to "false"
This is a common issue when using Singleton behavior with a IoC container such as Spring.NET or Windsor. Controllers should not have singleton behavior because the ControllerContext is per request, much like HttpContext.
Related
I have just spent 2 hours trying to work out why when I put a string in to View.Bag/ViewData inside my Surface controller, when I try and get the string back in the view I get null.
In the end I have solved the problem by putting the string in to a session variable insted.
Would like to know though why it wasn't working, and how to fix it.
Thanks in advance.
Update: Are you posting and redirecting? When you refresh the form does it prompt you about posting again? If not, it's because you have accidentally followed the best practice of 302ing from a form post (prevents a user refreshing and reposting form data). The examples I was following for login surface controllers all used return RedirectToCurrentUmbracoPage() which I blindly followed. But, as the name implies that really is doing a redirect and it is really two requests! (I stubbornly had to verify in Fiddler before I believed it). ViewData and ViewBag are only good for one request--so they are fundamentally broken in a POST 302. Session is good for multiple requests which is why it worked for you. TempData will work for you too, because as it turns out, TempData is a construct that is built on top of session and was specifically designed to carry state between two posts (removed on retrieve). I read somewhere that TempData would have been better named RedirectData and that helped it click for me.
So when you're dealing with Surface Controllers and POSTing you have three options that I know work:
Session (which you proved worked)
TempData (which is built on session, and from what I've read is both best practice and built specifically for this situation)
Use return CurrentUmbracoPage(); in your form post. I just verified in Fiddler that this is exactly one request (refreshing in the browser prompts a repost warning). I also verified that ViewData works this way. But, because the surface controller is rendered as a Child Action using #Html.Action(...) you have to use ParentActionViewContext to get at the right ViewData (my first answer which I'll leave for others that find this question).
Original answer is still useful when there is no redirect involved (GET or a POST that returns CurrentUmbracoPage())...
In many cases you're actually making a child action. Usually you're only one level deep but if you mix macros and partials you can actually get multiple levels deep. There is a ViewData for each level and you have to walk your way up the stack with ParentActionViewContext to get to the top ViewData that you populated in your controller.
See this comment from Shannon in answer to a question about surface controllers and viewdata (Shannon is a core contributor on the HQ team and has a lot of great content out there). Quoting here:
If you want to access the ViewData that you've set on the master ViewContext's on a ChildAction being rendered from the master's ViewContext then you need to use #ViewContext.ParentActionViewContext.ViewData["ErrorMessage"]
The ParentActionViewContext in this example is the ViewContext that is rendering the Umbraco template, not the ChildAction. That is because when you POST (whether inside of Umbraco or normal MVC), you are posting to a new Action and the rendering process starts from scratch, when you validate your model, update the ViewData, etc... this all happens on what will become the 'master' ViewContext when the view renders. This view then will render your ChildAction.
Twamley's answer above is excellent, in addition to this, I have found that using TempData.Add(key, value) works nicely.
An bare bones would look like:
SurfaceController
public class MyController : Umbraco.Web.Mvc.SurfaceController
{
public MyController()
{}
public ActionResult DoSomething()
{
// surface controller does something
// get a page by it's document/model type alias
var umbracoHelper = new UmbracoHelper(UmbracoContext.Current);
var node = umbracoHelper.TypedContentSingleAtXPath("//" + "Home")
TempData.Add("Message", "This value will be passed through");
return redirectToUmbracoPage(node);
}
}
View
#inherits UmbracoTemplatePage
#{
Layout = null;
}
#if (TempData.ContainsKey("Message"))
{
<p>#TempData["Message"]</p>
}
http://localhost/umbraco/Surface/My/DoSomething
I wanted to put a random image on every viewpage of my mvc project. So i created a method that returns a partialView and call that method in the shared Layout page.
This works fine when I try to login with a correct username and password. The used is loged in and every page contains a random image. But when I give the invalid combination of username and password. The shared layout page does not find the controller I want to call with my #Html.Action and actualy the login view should be returned with an error message 'invalid combination of username and password' and ofcourse, with the random image.
InnerException:
{"A public action method 'RandomSponsor' was not found on controller 'Project.WebUI.Controllers.HomeController'."}
My Html.Action in shared layout.
#Html.Action("RandomSponsor", "Home")
Method in homecontroller.
[HttpGet]
[ChildActionOnly]
public ActionResult RandomSponsor()
{
var model = service.getRandomSponsor();
return PartialView("RandomSponsor", model);
}
The getRandomSponsor method works fine, this one always returns one random string value that is returned to the RandomSponsor.cshtml view.
RandomSponsor.schtml (only contains the image string)
<img src="~/Content/Images/Advert/#(Model)" alt="a" />
I searched the web for this problem but didn't found a solution, does anyone know the answer to this one?
Might it be something with HttpGet of HttpPost?
Regards.
If the executing request is a POST, then it will try to find a method RandomSponsor accepting HttpPost. If this makes sense, you could remove HttpGet and that should do the trick.
This can also happen if you have many layers of calls that start with a POST (I had an action returning a view returning a partial view calling RenderAction), then the call to RenderAction will still look for a POST method
Very similar to this problem that I had here - How to solve "public action method 'methodActionName' was not found on controller 'controllerNameController'"
And if you want to continue to accept the HTTP GET verb and fix the problem of cascading post request into a get request add this to your method
[AcceptVerbs(HttpVerbs.Get | HttpVerbs.Post)]
Keep in mind that [HttpGet] is the same as [AcceptVerbs(HttpVerbs.Get)]
This will happen if the request is a POST but the controller method is annotated [HttpGet]. For example, you might issue a POST that returns a view containing partial views called with #Html.Action, using controller methods annotated with [HttpGet]. If the original request is a POST, all of the controller methods subsequently called will need to support POST.
To fix it you can use the AcceptVerbs attribute to specify that your controller method accepts both POST and GET:
[AcceptVerbs(HttpVerbs.Post | HttpVerbs.Get)]
Received this error all of the sudden on several different PartialViews (not all of them) when customizing an install of MVCForum. We had not made any changes to the methods or views concerning the errors so it was really frustrating as to why they were broken.
After trying the other solutions on this post and others, went back through the changes made and what ended up stopping the errors was that we had changed the bindings in IIS to another domain that had the 'enforce lower case url' URL Rewrite rule enabled.
When we disabled the enforce lowercase rule, the errors stopped and the site worked as it was supposed to. It's not a URL Rewrite issue (I don't think) because we are able to enforce www using it with no errors. It's a lowercase rewrite issue. Didn't matter if we had the lowercase rule before or after the www rule.
This solution probably doesn't apply to many cases of this error, but it worked for us. Hopefully someone else can benefit from such a simple fix.
I just solved this issue strangely enough on my local PC, by making sure my entire request path was lower case. So give that a try.
I know this is a pretty old thread - but as it's top Google result I thought I'd add a potentially missing link for MVC.Net 5.2.6.
Scenario
I was attempting to call a child action via #Html.Action("ActionName", new { Id = 123})
and received an error much like the above, but none of the other solutions worked. I could hit the controller action externally (i.e. HttpGet), but the child action kept throwing the exception and was driving me nuts!
The solution I found
After two-ing and fro-ing for some time, I started playing with my routing attributes. I had the controller set up as:
[Route("{action}")]
[RoutePrefix("Prefix")]
[RouteArea("AreaName")]
As there was only one public action i wanted, "Index", I removed the {action} and placed an explicit route attribute on the public action and put my ChildActionOnly attribute back on the child.
After I did that, I hit the run and hey presto - the action was hit.
Might be worth a try if you're getting this error while using attribute routing. Note I did attempt to route the child action and this didn't work.
In my case, the same issue was happening randomly with the implicit :
using (Html.BeginForm())
Changing above to :
using (Html.BeginForm("Action","Controller", FormMethod.Post))
fixed this issue.
Did you give it a shot with Html.RenderAction? It is typically faster then Html.Action as it interact directly into the response stream as opposed to building a string.
You can view the following topics for more info:
What is the difference (if any) between Html.Partial(view, model) and Html.RenderPartial(view,model) in MVC2?
Html.Partial vs Html.RenderPartial & Html.Action vs Html.RenderAction
Another thing to note is that for Html.Action or Html.RenderAction, your view doesn't need to be in Shared folder, that is only required if you use Html.Partial or Html.RenderPartial
I've been implementing a RouteConstraint recently whos responsibility is to Match a custom route value against some model data that is in the session.
What I've found is that the session is null for the routeDirection of IncomingRequest.
Is the session not configured until
the controller is
created/initialized?
If this is the case, is this type of
function better suited to a filter
applied at the controller level?
Are there any other viable options?
The shame of it is that this validation does need to be applied on every route except for when the session is configured on first entry, so I thought a route constraint would be the best solution.
Thanks.
Since it has to happen on pretty much each call I would probably handle the controller's (or base controller's) OnActionExecuting and then set the ActionExecutingContext.Result to return a new RedirectToRouteResult with a RouteValueDictionary that contains the values you need. This could be encapsulated in an ActionFilter as well (controller implements IActionFilter).
It is not clear to me what exactly you are trying to implement (redirection to login page or rendering some message) so I can't give any good alternative solution but I can tell you that session is not accessible when IRouteConstraint is being evaluated because routing pipeline happens before session is loaded. E.g. routing might render page that doesn't require session at all.
what are your top lessons learned when starting asp.net mvc that you would highlight to someone starting out so they can avoid these mistakes?
Use Html.Encode() everywhere you print data, unless you have a very good reason to not do so, so you don't have to worry about XSS
Don't hardcode routes into your views or javascripts - they're going to change at some point, use Url.Action() instead
Don't be afraid of using partial views
MVC is no silver bullet, first evaluate if it's indeed the best tool of choice for solving your problem.
Don't forget the "Unit Tests" part of the pattern.
Try to always use a ViewModel to pass data between the Controller and the View.
You may think you don't need one, you can just pass your model around, but suddenly you need a list box with several options for editing a model, or displaying a message (not validation message) and you start adding items to the ViewData, with magic strings as keys, making the app harder to maintain.
There are also some security issues that you solve with a ViewModel.
For instance:
class user:
int id
string name
string email
string username
string password
Your view let's the user change his name and email and posts to the action
public ActionResult Edit(User user)
{
--persist data
}
Someone could tamper your form and post a new password and username and you will need to be very careful with the DefaultBinder behavior.
Now, if you use a ViewModel like:
class userEditViewModel:
int id
string name
string email
The problem is gone.
Whenever it is possible make your view typed
Avoid logic in your views
stay away from the HttpContext
Get Steve Sandersons Pro ASP.NET MVC Framework
Debug into the Sourcecode
If you make a Controller method with a different parameter name from id for a single parameter method, you have to make a new route. Just bite the bullet and use id (it doesn't care about the type) and explain it in the comments.
Makes sure you name your parameters with RedirectToAction :
return RedirectToAction("DonateToCharity", new { id = 1000 });
You lose your ViewData when you RedirectToAction.
Put javascript in seperate files, not into the view page
name of the controller :)
unit test Pattern
Don't use the Forms collection, use model binding.
Try not to use ViewData, create a ViewModel.
If you have a loop or an if in your View, write an HTML helper.
Kindness,
Dan
Don't let your controller become a fat one and do too much work. I've seen 1000+ line controllers in the past and it just becomes an absolute nightmare to understand what's going.
Utilise unit testing for your controllers to ensure that dependencies are kept under control and that your code is testable.
Don't get drawn into letting jQuery and fancy clientscript define the behaviour of your application, try and use it as sparingly as you can and let it enhance your application instead.
Use partial views and HTML helpers whenever possible to ensure that your Views do not become unwieldy and a maintenance nightmare.
Use a ViewModel whenever possible.
Use a dependency injection framework to handle your dependencies (MvcContrib has several controller factories, though it's simple enough to roll your own).
Use a different controller for every section of your site (e.g., Home, Account)
Learn how to use ViewData and TempData
Learn what's the use of RenderPartial
I have a value which I want to be vaild during a single request. I am not using Session, as this would make the value global for the entire navigation session.
So I have put thie value in a static field of a class. Great, but then I discovered that such fields are even more global, that is, they stay set for the entire application! This means that there could be random interaction among navigation sessions.
So the question is: is there a safe place I can put a global variable, which will be
global throughout the request
reset after the request is completed
not affected by any other request, either of the same user or by other users
Thanks
Palantir
EDIT
I'll elaborate. I have a piece of code in my master page, which I need to hide on certain conditions, of which I am aware in the controller only. I thought about setting a static variable in the controller, which then would be queried by the master page, but now I see there could be a better way...
Use HttpContext.Items - a per-request cache store. Check out this article on 4guysfromrolla for more details.
It should work fine in ASP.NET MVC. You may wish to derive your master page from a base class (either via code-behind or using the Inherits directive) and have a protected method on the base class that inspects HttpContext.Items and returns, e.g. true/false depending whether you want to display the conditional code.
TempData lasts until the next request as already noted.
But there are also two other dictionaries scoped to the single request.
{Controller,ViewPage}.ViewData
Context.Items
To communicate from controller to (master) page ViewData is probably the better choice.
Two approaches come to mind:
Create a base controller where you set this variable, and then have all your controllers inherit from that.
Use TempData - the problem here being that it sticks around for the next request. But maybe knowing that, you can work around it by using a GUID key to determine that you are, in fact, getting a new value when you need it.
I would probably go with 1).
The common way to access data in a MasterPage that is set in Controller (Action) is via ViewData["TheDataKey"] = "SomeValue".
This is relatively easy and there are a couple of ways that you can do it - depending on how your site works.
I'm interpreting your request as that you want a property or variable that exists for the duration of the request and is visible to the controller, model and master.
A static property is visible to the current application in ASP this means a load of users connecting at once, but not necessarily all of them. IIS will spawn new ASP applications as it needs to.
So the ways you can do this:
You can have a custom base class for your master page or a code-behind page (as all the WebForms stuff still works)
You can have a custom base class for your controllers.
You can get to one from the other, so:
void Page_Init( object sender, EventArgs e )
{
var ctrl = this.ViewContext.Controller as MyBaseController;
if ( ctrl != null )
{
MyLocalProp = ctrl.PropOnMyController;
}
}
This will then be available in the controller and the master page on a per Request basis.
Did you look into the tempData that is attached to the controller class? it is a simple dictionary that preserves it's value through one single request.That would meant that your data can only be accessed in the controller but that should not be a problem.
public class MyController : Controller
{
[AcceptVerbs(HttpVerbs.Get)]
public ActionResult MyAction(string id)
{
this.TempData["Message"] = "YourData";
}
[AcceptVerbs(HttpVerbs.Post)]
public ActionResult MyAction(string Id)
{
var myData = this.TempData["Message"];
}
}
This works for me. I use it only to display warning messages and stuff like that.