Accessing ASP.NET MVC Action Parameters - asp.net-mvc

This must be simple, but I can't seem to figure it out. I am setting an action parameter inside an action filter as follows:
public class MyFilter : ActionFilterAttribute
{
public override void OnActionExecuting (ActionExecutingContext filterContext)
{
filterContext.ActionParameters["MyParam"] = "MyValue";
}
}
I am applying the filter to an entire controller as follows:
[MyFilter]
public class HomeController : Controller
{
public ActionResult Index()
{
// How do I access MyParam here?
return View();
}
}
}
How do I access MyParam inside an action method?

Maybe you could use:
[MyFilter]
public ActionResult Index(string MyParam)
{
//Do something with MyParam
return View();
}
You can decorate whole controller with [MyFilter] or only one action.

I'm hoping this will work:
var myParam = ValueProvider.GetValue("MyParam").RawValue as string;
Since ValueProvider is what modelbinders use to get the values I would think it should be able to get the value set in your filter.

Related

How to declare controller action method return type?

I understand ActionResult is the base class for RedirectResult class so essentially functionality for the code below is the same.
Is there an advantage to explicitly specify the appropriate result class as a return type as opposed to the base class?
public ActionResult Index()
{
return Redirect("Home/Contact");
}
public RedirectResult Index()
{
return Redirect("Home/Contact");
}
if you need redirect quickly to another action without lost any data and this action is in the same controller , call the action as a method:
public IActionResult Index()
{
return Contact();
}
public IActionResult Contact()
{
....
}
which one from another redirections methods is better is an opinion-based question and is not allowed by SO policy

MVC Routes data not available

I have a controller called BaseController. In the BaseController, I have an Action method called Index which has some logic that involves querying the routes and building the URLs. Something on the lines of:
var link = Url.RouteUrl("myroute", new { id = 5 });
All this is well and fine until I create a controller NewController that extends the BaseController. In the constructor of NewController, I pass BaseController as a dependency.
public class NewController
{
private BaseController _baseController;
public NewController(BaseController baseController)
{
_baseController = baseController;
}
public ActionResult Index()
{
return _baseController.Index();
}
}
Reason why this was needed was because I need to override the view (some HTML and CSS changes). I didn't want to recreate the models and services and rewrite the business logic, so thought this would be the best and most time-effective approach.
Only issue is when the BaseController's Index Action is called, the Url is null obviously. Routes data is not available because the request was generated outside the base controller.
What is the best way to get around this?
Make BaseController.Index() virtual:
public class BaseController : Controller
{
public virtual ActionResult Index()
{
return View();
}
}
Then use inheritance:
public class NewController : BaseController
{
public override ActionResult Index()
{
var index = base.Index();
//do whatever
return index;
}
}
You are trying to call action method from another controller. Propably your constructor method gets baseController as a null. can you try to implement it like following
public ActionResult Index()
{
return new BaseController().Index(); // assume you call index action
}
Or you can call BaseController action from another controller like following
public ActionResult Index()
{
return RedirectToAction("Index", "Base"); // assume you call index action
}
You can also change Route url like following.
#Url.RouteUrl("myroute", new { controller = "Base", action = "Index", id = 5 })
I have another solution that requires a little bit of code design efforts.
Why don't you Abstract your business logic away from the two Controllers?
For example: RouteBuilder.cs a class that have the functions that contains the logic of building the routes.
And BaseClass.cs is a class that contains the Logic shared between the two Controllers.
Then:
public class BaseController
{
public ActionResult Index()
{``
//Instantiase BaseClass.cs and call the needed functions. Then RouteBuilder.cs and call functions.
return View();
}
}
public class NewController
{
public ActionResult Index()
{``
//Instantiase BaseClass.cs and call the needed functions.
return View();
}
}
Viola. Problem solved and clean code produced.

Asp.Net MVC How to log all actions being called

I need to be able to log all actions that are called from my asp.net mvc application. How and what would be the best way to achieve this? Where I log it to whether it be the console or log file doesn't matter.
You could create your own class which inherits from ActionFilterAttribute and then override the OnActionExecuting method.
Example
public class LogActionAttribute : ActionFilterAttribute
{
public override void OnActionExecuting(ActionExecutingContext filterContext)
{
var controller = filterContext.RequestContext.RouteData.Values["Controller"];
var action = filterContext.RequestContext.RouteData.Values["Action"];
//
// Perform logging here
//
base.OnActionExecuting(filterContext);
}
}
public class HomeController : Controller
{
[LogAction]
public ActionResult Index()
{
return View();
}
}
Hope this helps!
Credit HeyMega for their answer. Here's an example of an expanded implementation I arrived at in MVC5.
public class LogActionAttribute : ActionFilterAttribute
{
public override void OnActionExecuting(ActionExecutingContext filterContext)
{
var controller = filterContext.RequestContext.RouteData.Values.ContainsKey("Controller") ? filterContext.RequestContext.RouteData.Values["Controller"].ToString() : null;
var action = filterContext.RequestContext.RouteData.Values.ContainsKey("Action") ? filterContext.RequestContext.RouteData.Values["Action"].ToString() : null;
var area = filterContext.RequestContext.RouteData.DataTokens.ContainsKey("Area") ? filterContext.RequestContext.RouteData.DataTokens["Area"].ToString() : null;
var user = filterContext.RequestContext.HttpContext.User.Identity.GetUserId();
Task.Run(() => Generic().AreaActionLog(user, area, controller, action));
base.OnActionExecuting(filterContext);
}
}
I chose to separate the method doing the actual logging into a separate process, if anything goes wrong with the Database interaction, or the DB interaction takes several seconds, the UI is uninterrupted.
You can then decorate the entire controller with [LogAction] attribute like so.
[LogAction]
public class HomeController : Controller
{
public ActionResult Index()
{
return View();
}
public ActionResult Contact()
{
return View();
}
}
Or selectively apply the attribute by decorating individual methods:
public class HomeController : Controller
{
[LogAction]
public ActionResult Index_Logs_Things()
{
return View();
}
}
Hope this helps someone.
You could try Audit.NET library with its Audit.MVC and the different data providers to store the logs on files, eventlog, sql, redis, mongo, and much more.
With the MVC extension you just need to decorate your controllers or actions with an attribute:
[Audit]
public class HomeController : Controller
{ ... }
Execute a static configuration to set the output of your logs:
Audit.Core.Configuration.Setup()
.UseFileLogProvider(_ => _
.Directory(#"C:\Logs"));
And it will provide the infrastructure to log the interactions with your MVC application.

ControllerContext is null and BaseController.OnActionExecuting() not called when using Html.Action

We use a BaseController to cache basic authentication information before every action executes:
public abstract class BaseController : Controller
{
protected bool IsLoggedIn { get; set; }
protected string Username { get; set; }
...
protected override void OnActionExecuting(ActionExecutingContext filterContext)
{
var identity = base.User.Identity;
this.IsLoggedIn = identity.IsAuthenticated;
this.Username = identity.Name;
...
}
}
And our child controller has a actions for the main page (Index) and a partial view (GetNavigation):
[Authorize]
public partial class CollaborationController : BaseController
{
[HttpGet]
public virtual ViewResult Index()
{
var viewModel = this.MakeViewModel<FullPageViewModel>();
return this.View(MVC.Collaboration.Views.Index, viewModel);
}
[HttpGet]
public virtual PartialViewResult GetNavigation()
{
var viewModel = NavigationViewModel.Make(this.User);
return this.PartialView(MVC.Collaboration.Views.Navigation, viewModel);
}
}
And the partial view is rendered directly with Html.Action():
#Html.Action(MVC.Collaboration.GetNavigation())
Seems like it should work, but BaseController.OnActionExecuting does not get called. And I can't even call it directly because this.ControllerContext and base.User are both null. I also tried subclassing ActionFilterAttribute, but its OnActionExecuting method doesn't get called, either.
I know this is an old question but here is how I handle this. In my child controller I create the OnActionExecuting method and call the base controller from there.
protected override void OnActionExecuting(ActionExecutingContext filterContext)
{
base.OnActionExecuting(filterContext);
}
At least sort-of answered my own question:
Substituting
#Html.Action("GetNavigation", "Collaboration")
for
#Html.Action(MVC.Collaboration.GetNavigation())
fixes it. MVCContrib's syntax seems to be the culprit, anyone know why? Even better, anyone know a work-around that lets me avoid those nasty, non-refactoring-safe, magic strings?

Routing to the actions with same names but different parameters

I have this set of routes:
routes.MapRoute(
"IssueType",
"issue/{type}",
new { controller = "Issue", action = "Index" }
);
routes.MapRoute(
"Default", // Route name
"{controller}/{action}/{id}", // URL with parameters
new { controller = "Home", action = "Index", id = UrlParameter.Optional } // Parameter defaults
);
Here is the controller class:
public class IssueController : Controller
{
public ActionResult Index()
{
// todo: redirect to concrete type
return View();
}
public ActionResult Index(string type)
{
return View();
}
}
why, when i request http://host/issue i get The current request for action 'Index' on controller type 'IssueController' is ambiguous between the following action methods:
I expect that first one method should act when there is no parameters, and second one when some parameter specified.
where did i made mistake?
UPD: possible duplicate: Can you overload controller methods in ASP.NET MVC?
UPD 2: due to the link above - there is no any legal way to make action overloading, is it?
UPD 3: Action methods cannot be overloaded based on parameters (c) http://msdn.microsoft.com/en-us/library/system.web.mvc.controller%28VS.100%29.aspx
I would have one Index method that looks for a valid type variable
public class IssueController : Controller
{
public ActionResult Index(string type)
{
if(string.isNullOrEmpty(type)){
return View("viewWithOutType");}
else{
return View("viewWithType");}
}
}
EDIT:
How about creating a custom attribute that looks for a specific request value as in this post StackOverflow
[RequireRequestValue("someInt")]
public ActionResult MyMethod(int someInt) { /* ... */ }
[RequireRequestValue("someString")]
public ActionResult MyMethod(string someString) { /* ... */ }
public class RequireRequestValueAttribute : ActionMethodSelectorAttribute {
public RequireRequestValueAttribute(string valueName) {
ValueName = valueName;
}
public override bool IsValidForRequest(ControllerContext controllerContext, MethodInfo methodInfo) {
return (controllerContext.HttpContext.Request[ValueName] != null);
}
public string ValueName { get; private set; }
}
I ran into a similar situation where I wanted my "Index" action to handle the rendering if I had an ID specified or not. The solution I came upon was to make the ID parameter to the Index method optional.
For example, I originally tried having both:
public ViewResult Index()
{
//...
}
// AND
public ViewResult Index(int entryId)
{
//...
}
and I just combined them and changed it to:
public ViewResult Index(int entryId = 0)
{
//...
}
You can do it using an ActionFilterAttribute that checks the parameters using reflection (I tried it) but it's a bad idea. Each distinct action should have its own name.
Why not just call your two methods "Index" and "Single", say, and live with the limitation on naming?
Unlike methods that are bound at compile time based on matching signatures, a missing route value at the end is treated like a null.
If you want the [hack] ActionFilterAttribute that matches parameters let me know and I'll post a link to it, but like I said, it's a bad idea.
All you have to do is mark your second Action with [HttpPost]. For instance:
public class IssueController : Controller
{
public ActionResult Index()
{
// todo: redirect to concrete type
return View();
}
[HttpPost]
public ActionResult Index(string type)
{
return View();
}
}

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