I have this controller in an MVC 5 WebAPI application and I can't seem to figure out how to form the URL to call it. I keep getting a 404. tried .../ssa, /ssa/ssamedians, /ssa/ssamedians?titles=abc... What am I missing?
public class ssaController : ApiController
{
public IHttpActionResult getSsaMedians(string Titles = "")
{
SsaDB db = new SsaDB();
try
{
IEnumerable<Title_Medians> medians = db.getTitleMedians(Titles, null, null);
System.Web.HttpContext.Current.Response.AppendHeader("Access-Control-Allow-Origin", "*");
return Ok(medians);
}
catch
{
return NotFound();
}
}
There are also Actions called getSsaMediansByAaa() and getSsaMediansByBbb(). Once I got rid of the api/ in the routeTemplate, I now get a "Multiple actions were found that match the request".
Open your WebApiConfig.cs file and add this:
config.Routes.MapHttpRoute(
name: "SSATitles",
routeTemplate: "api/{controller}/{action}/{Titles}",
defaults: new { controller = "ssa", action = "getSsaMedians", Titles = UrlParameter.Optional }
);
For more information on webapi routing look here:
http://www.asp.net/web-api/overview/web-api-routing-and-actions/routing-in-aspnet-web-api
You have an parameter in your method, that means that you need to add an extra link in your url.
Examlple.com/DirToApi/getSsaMedians/YourString
You may also want to check your RouteConfig file in your App_Start
On my site, I have moved some images from one folder to another.
Now, when I receive a request for old images '/old_folder/images/*' I want to make a permanent redirect to new folder with these images '/new_folder/images/*'
For example:
/old_folder/images/image1.png => /new_folder/images/image1.png
/old_folder/images/image2.jpg => /new_folder/images/image2.jpg
I have added a simple redirect controller
public class RedirectController : Controller
{
public ActionResult Index(string path)
{
return RedirectPermanent(path);
}
}
Now I need to setup proper routing, but I don't know how to pass the path part to the path parameter.
routes.MapRoute("ImagesFix", "/old_folder/images/{*pathInfo}", new { controller = "Redirect", action = "Index", path="/upload/images/????" });
Thanks
I would do in next way
routes.MapRoute("ImagesFix", "/old_folder/images/{path}", new { controller = "Redirect", action = "Index" });
and in controller like that
public class RedirectController : Controller
{
public ActionResult Index(string path)
{
return RedirectPermanent("/upload/images/" + path);
}
}
first download and install RouteMagic package from this link , then redirect your old address to the new address Like the below code :
var NewPath = routes.MapRoute("new", "new_folder/images/{controller}/{action}");
var OldPath = routes.MapRoute("new", "old_folder/images/{controller}/{action}");
routes.Redirect(OldPath ).To(NewPath );
for more information please check out the following link
Redirecting Routes To Maintain Persistent URLs
Answer above using RouteMagic is a good idea, but the example code is wrong (it's included in Phil's post as a bad example).
From the RouteMagic Github demo site global.asax.cs:
// Redirect From Old Route to New route
var targetRoute = routes.Map("target", "yo/{id}/{action}", new { controller = "Home" });
routes.Redirect(r => r.MapRoute("legacy", "foo/{id}/baz/{action}")).To(targetRoute, new { id = "123", action = "index" });
If you specify two routes, you will be setting up an extra mapping that will catch URLs which you don't want.
I have got a legacy url that I cannot change, which is output on a page which needs to now post to a new MVC version of the page:
http://somesite.com/somepage?some-guid=xxxx-xxxx
Now I am trying to map this to a new controller but I need to get the some-guid into my controller:
public class MyController : Controller
{
[HttpGet]
public ActionResult DisplaySomething(Guid myGuid)
{
var someResult = DoSomethingWithAGuid(myGuid);
...
}
}
I can change the controller and routes as much as I like, however the legacy url cannot change. So I am a bit stumped as to how I can get access to the some-guid.
I have tried routing with the ?some-guid={myGuid} but the routing doesn't like the ?, so then I tried to let it autobind, but as it contains hyphens it doesn't seem to bind. I was wondering if there was any type of attribute I could use to hint that it should bind from a part of the querystring...
Any help would be great...
I would have thought you would have done a route a bit like this..
routes.MapRoute(
"RouteName", // Name the route
"somepage/{some-guid}", // the Url
new { controller = "MyController", action = "DisplaySomething", some-guid = UrlParameter.Optional }
);
The {some-guid} part of URL matches your url parmater and passes it to the controller.
So if you have your action like so :
public ActionResult DisplaySomething(Guid some-guid)
{
var someResult = DoSomethingWithAGuid(some-guid);
...
}
Give that a go and see how you get on..
routes.MapRoute(
"Somepage", // Route name
"simepage", // URL with parameters
new { controller = "MyController", action = "DisplaySomething"
);
And then in your controller:
public class MyController : Controller {
public ActionResult DisplaySomething(Guid myGuid)
{
var someResult = DoSomethingWithAGuid(myGuid);
...
}
}
Try this:
routes.MapRoute("SomePageRoute","Somepage",
new { controller = "MyController", action = "DisplaySomething" });
And then in your controller:
public ActionResult DisplaySomething() {
Guid sGuid = new Guid(Request.QueryString["some-guid"].ToString());
}
Can anyone give me a succinct definition of the role of ModelState in Asp.net MVC (or a link to one). In particular I need to know in what situations it is necessary or desirable to call ModelState.Clear().
Bit open ended huh... sorry, I think it might help if tell you what I'm acutally doing:
I have an Action of Edit on a Controller called "Page". When I first see the form to change the Page's details everything loads up fine (binding to a "MyCmsPage" object). Then I click a button that generates a value for one of the MyCmsPage object's fields (MyCmsPage.SeoTitle). It generates fine and updates the object and I then return the action result with the newly modified page object and expect the relevant textbox (rendered using <%= Html.TextBox("seoTitle", page.SeoTitle)%>) to be updated ... but alas it displays the value from the old model that was loaded.
I've worked around it by using ModelState.Clear() but I need to know why / how it has worked so I'm not just doing it blindly.
PageController:
[AcceptVerbs("POST")]
public ActionResult Edit(MyCmsPage page, string submitButton)
{
// add the seoTitle to the current page object
page.GenerateSeoTitle();
// why must I do this?
ModelState.Clear();
// return the modified page object
return View(page);
}
Aspx:
<%# Page Language="C#" MasterPageFile="~/Views/Shared/Site.Master" Inherits="System.Web.Mvc.ViewPage<MyCmsPage>" %>
....
<div class="c">
<label for="seoTitle">
Seo Title</label>
<%= Html.TextBox("seoTitle", page.SeoTitle)%>
<input type="submit" value="Generate Seo Title" name="submitButton" />
</div>
I think is a bug in MVC. I struggled with this issue for hours today.
Given this:
public ViewResult SomeAction(SomeModel model)
{
model.SomeString = "some value";
return View(model);
}
The view renders with the original model, ignoring the changes. So I thought, maybe it does not like me using the same model, so I tried like this:
public ViewResult SomeAction(SomeModel model)
{
var newModel = new SomeModel { SomeString = "some value" };
return View(newModel);
}
And still the view renders with the original model. What's odd is, when I put a breakpoint in the view and examine the model, it has the changed value. But the response stream has the old values.
Eventually I discovered the same work around that you did:
public ViewResult SomeAction(SomeModel model)
{
var newModel = new SomeModel { SomeString = "some value" };
ModelState.Clear();
return View(newModel);
}
Works as expected.
I don't think this is a "feature," is it?
Update:
This is not a bug.
Please stop returning View() from a POST action. Use PRG instead and redirect to a GET if the action is a success.
If you are returning a View() from a POST action, do it for form validation, and do it the way MVC is designed using the built in helpers. If you do it this way then you shouldn't need to use .Clear()
If you're using this action to return ajax for a SPA, use a web api controller and forget about ModelState since you shouldn't be using it anyway.
Old answer:
ModelState in MVC is used primarily to describe the state of a model object largely with relation to whether that object is valid or not. This tutorial should explain a lot.
Generally you should not need to clear the ModelState as it is maintained by the MVC engine for you. Clearing it manually might cause undesired results when trying to adhere to MVC validation best practises.
It seems that you are trying to set a default value for the title. This should be done when the model object is instantiated (domain layer somewhere or in the object itself - parameterless ctor), on the get action such that it goes down to the page the 1st time or completely on the client (via ajax or something) so that it appears as if the user entered it and it comes back with the posted forms collection. Some how your approach of adding this value on the receiving of a forms collection (in the POST action // Edit) is causing this bizarre behaviour that might result in a .Clear() appearing to work for you. Trust me - you don't want to be using the clear. Try one of the other ideas.
If you want to clear a value for an individual field then I found the following technique useful.
ModelState.SetModelValue("Key", new ValueProviderResult(null, string.Empty, CultureInfo.InvariantCulture));
Note:
Change "Key" to the name of the field that you want to reset.
Well lots of us seem to have been bitten by this, and although the reason this happens makes sense I needed a way to ensure that the value on my Model was shown, and not ModelState.
Some have suggested ModelState.Remove(string key), but it's not obvious what key should be, especially for nested models. Here are a couple methods I came up with to assist with this.
The RemoveStateFor method will take a ModelStateDictionary, a Model, and an expression for the desired property, and remove it. HiddenForModel can be used in your View to create a hidden input field using only the value from the Model, by first removing its ModelState entry. (This could easily be expanded for the other helper extension methods).
/// <summary>
/// Returns a hidden input field for the specified property. The corresponding value will first be removed from
/// the ModelState to ensure that the current Model value is shown.
/// </summary>
public static MvcHtmlString HiddenForModel<TModel, TProperty>(this HtmlHelper<TModel> helper,
Expression<Func<TModel, TProperty>> expression)
{
RemoveStateFor(helper.ViewData.ModelState, helper.ViewData.Model, expression);
return helper.HiddenFor(expression);
}
/// <summary>
/// Removes the ModelState entry corresponding to the specified property on the model. Call this when changing
/// Model values on the server after a postback, to prevent ModelState entries from taking precedence.
/// </summary>
public static void RemoveStateFor<TModel, TProperty>(this ModelStateDictionary modelState, TModel model,
Expression<Func<TModel, TProperty>> expression)
{
var key = ExpressionHelper.GetExpressionText(expression);
modelState.Remove(key);
}
Call from a controller like this:
ModelState.RemoveStateFor(model, m => m.MySubProperty.MySubValue);
or from a view like this:
#Html.HiddenForModel(m => m.MySubProperty.MySubValue)
It uses System.Web.Mvc.ExpressionHelper to get the name of the ModelState property.
Well the ModelState basically holds the current State of the model in terms of validation, it holds
ModelErrorCollection: Represent the errors when the model try to bind the values.
ex.
TryUpdateModel();
UpdateModel();
or like a parameter in the ActionResult
public ActionResult Create(Person person)
ValueProviderResult: Hold the details about the attempted bind to the model.
ex. AttemptedValue, Culture, RawValue.
Clear() method must be use with caution because it can lead to unspected results. And you will lose some nice properties of the ModelState like AttemptedValue, this is used by MVC in the background to repopulate the form values in case of error.
ModelState["a"].Value.AttemptedValue
I had an instance where I wanted to update the model of a sumitted form, and did not want to 'Redirect To Action' for performanace reason. Previous values of hidden fields were being retained on my updated model - causing allsorts of issues!.
A few lines of code soon identified the elements within ModelState that I wanted to remove (after validation), so the new values were used in the form:-
while (ModelState.FirstOrDefault(ms => ms.Key.ToString().StartsWith("SearchResult")).Value != null)
{
ModelState.Remove(ModelState.FirstOrDefault(ms => ms.Key.ToString().StartsWith("SearchResult")));
}
I wanted to update or reset a value if it didn't quite validate, and ran into this problem.
The easy answer, ModelState.Remove, is.. problematic.. because if you are using helpers you don't really know the name (unless you stick by the naming convention). Unless perhaps you create a function that both your custom helper and your controller can use to get a name.
This feature should have been implemented as an option on the helper, where by default is does not do this, but if you wanted the unaccepted input to redisplay you could just say so.
But at least I understand the issue now ;).
Got it in the end. My Custom ModelBinder which was not being registered and does this :
var mymsPage = new MyCmsPage();
NameValueCollection frm = controllerContext.HttpContext.Request.Form;
myCmsPage.SeoTitle = (!String.IsNullOrEmpty(frm["seoTitle"])) ? frm["seoTitle"] : null;
So something that the default model binding was doing must have been causing the problem. Not sure what, but my problem is at least fixed now that my custom model binder is being registered.
Generally, when you find yourself fighting against a framework standard practices, it is time to reconsider your approach. In this case, the behavior of ModelState. For instance, when you don't want model state after a POST, consider a redirect to the get.
[HttpPost]
public ActionResult Edit(MyCmsPage page, string submitButton)
{
if (ModelState.IsValid) {
SomeRepository.SaveChanges(page);
return RedirectToAction("GenerateSeoTitle",new { page.Id });
}
return View(page);
}
public ActionResult GenerateSeoTitle(int id) {
var page = SomeRepository.Find(id);
page.GenerateSeoTitle();
return View("Edit",page);
}
EDITED to answer culture comment:
Here is what I use to handle a multi-cultural MVC application. First the route handler subclasses:
public class SingleCultureMvcRouteHandler : MvcRouteHandler {
protected override IHttpHandler GetHttpHandler(RequestContext requestContext)
{
var culture = requestContext.RouteData.Values["culture"].ToString();
if (string.IsNullOrWhiteSpace(culture))
{
culture = "en";
}
var ci = new CultureInfo(culture);
Thread.CurrentThread.CurrentUICulture = ci;
Thread.CurrentThread.CurrentCulture = CultureInfo.CreateSpecificCulture(ci.Name);
return base.GetHttpHandler(requestContext);
}
}
public class MultiCultureMvcRouteHandler : MvcRouteHandler
{
protected override IHttpHandler GetHttpHandler(RequestContext requestContext)
{
var culture = requestContext.RouteData.Values["culture"].ToString();
if (string.IsNullOrWhiteSpace(culture))
{
culture = "en";
}
var ci = new CultureInfo(culture);
Thread.CurrentThread.CurrentUICulture = ci;
Thread.CurrentThread.CurrentCulture = CultureInfo.CreateSpecificCulture(ci.Name);
return base.GetHttpHandler(requestContext);
}
}
public class CultureConstraint : IRouteConstraint
{
private string[] _values;
public CultureConstraint(params string[] values)
{
this._values = values;
}
public bool Match(HttpContextBase httpContext,Route route,string parameterName,
RouteValueDictionary values, RouteDirection routeDirection)
{
// Get the value called "parameterName" from the
// RouteValueDictionary called "value"
string value = values[parameterName].ToString();
// Return true is the list of allowed values contains
// this value.
return _values.Contains(value);
}
}
public enum Culture
{
es = 2,
en = 1
}
And here is how I wire up the routes. After creating the routes, I prepend my subagent (example.com/subagent1, example.com/subagent2, etc) then the culture code. If all you need is the culture, simply remove the subagent from the route handlers and routes.
public static void RegisterRoutes(RouteCollection routes)
{
routes.IgnoreRoute("{resource}.axd/{*pathInfo}");
routes.IgnoreRoute("Content/{*pathInfo}");
routes.IgnoreRoute("Cache/{*pathInfo}");
routes.IgnoreRoute("Scripts/{pathInfo}.js");
routes.IgnoreRoute("favicon.ico");
routes.IgnoreRoute("apple-touch-icon.png");
routes.IgnoreRoute("apple-touch-icon-precomposed.png");
/* Dynamically generated robots.txt */
routes.MapRoute(
"Robots.txt", "robots.txt",
new { controller = "Robots", action = "Index", id = UrlParameter.Optional }
);
routes.MapRoute(
"Sitemap", // Route name
"{subagent}/sitemap.xml", // URL with parameters
new { subagent = "aq", controller = "Default", action = "Sitemap"}, new[] { "aq3.Controllers" } // Parameter defaults
);
routes.MapRoute(
"Rss Feed", // Route name
"{subagent}/rss", // URL with parameters
new { subagent = "aq", controller = "Default", action = "RSS"}, new[] { "aq3.Controllers" } // Parameter defaults
);
/* remap wordpress tags to mvc blog posts */
routes.MapRoute(
"Tag", "tag/{title}",
new { subagent = "aq", controller = "Default", action = "ThreeOhOne", id = UrlParameter.Optional}, new[] { "aq3.Controllers" }
).RouteHandler = new MultiCultureMvcRouteHandler(); ;
routes.MapRoute(
"Custom Errors", "Error/{*errorType}",
new { controller = "Error", action = "Index", id = UrlParameter.Optional}, new[] { "aq3.Controllers" }
);
/* dynamic images not loaded from content folder */
routes.MapRoute(
"Stock Images",
"{subagent}/Images/{*filename}",
new { subagent = "aq", controller = "Image", action = "Show", id = UrlParameter.Optional, culture = "en"}, new[] { "aq3.Controllers" }
);
/* localized routes follow */
routes.MapRoute(
"Localized Images",
"Images/{*filename}",
new { subagent = "aq", controller = "Image", action = "Show", id = UrlParameter.Optional}, new[] { "aq3.Controllers" }
).RouteHandler = new MultiCultureMvcRouteHandler();
routes.MapRoute(
"Blog Posts",
"Blog/{*postname}",
new { subagent = "aq", controller = "Blog", action = "Index", id = UrlParameter.Optional}, new[] { "aq3.Controllers" }
).RouteHandler = new MultiCultureMvcRouteHandler();
routes.MapRoute(
"Office Posts",
"Office/{*address}",
new { subagent = "aq", controller = "Offices", action = "Address", id = UrlParameter.Optional }, new[] { "aq3.Controllers" }
).RouteHandler = new MultiCultureMvcRouteHandler();
routes.MapRoute(
"Default", // Route name
"{controller}/{action}/{id}", // URL with parameters
new { subagent = "aq", controller = "Home", action = "Index", id = UrlParameter.Optional }, new[] { "aq3.Controllers" } // Parameter defaults
).RouteHandler = new MultiCultureMvcRouteHandler();
foreach (System.Web.Routing.Route r in routes)
{
if (r.RouteHandler is MultiCultureMvcRouteHandler)
{
r.Url = "{subagent}/{culture}/" + r.Url;
//Adding default culture
if (r.Defaults == null)
{
r.Defaults = new RouteValueDictionary();
}
r.Defaults.Add("culture", Culture.en.ToString());
//Adding constraint for culture param
if (r.Constraints == null)
{
r.Constraints = new RouteValueDictionary();
}
r.Constraints.Add("culture", new CultureConstraint(Culture.en.ToString(), Culture.es.ToString()));
}
}
}
Well, this seemed to work on my Razor Page and never even did a round trip to the .cs file.
This is old html way. It might be useful.
<input type="reset" value="Reset">
Has anyone else had this issue? I have to be doing something wrong.
So I'm setting up a route for errors like this:
routes.MapRoute
(
"SharedError",
"Shared/Error/{error}",
new { error = "" }
);
And calling like:
return parentController.RedirectToRoute("SharedError", new RouteValueDictionary(new { error = errorMessage.ToString() }));
And on the controller:
public ActionResult Error(String error)
Simple right? Well when this is actually run, error is null despite the url looking like:
/Shared/Error/ThisIsTheError
But the error parameter in the Error method is null. (And yes I've tried other words)
Now if I replace all that with the word 'id' everything works.
Global.asax.cs
routes.MapRoute
(
"SharedError",
"Shared/Error/{id}",
new { id = "" }
);
Redirect:
return parentController.RedirectToRoute("SharedError", new RouteValueDictionary(new { id = errorMessage.ToString() }));
Shared Controller:
public ActionResult Error(String id)
Is id a must have word for all routes if you have a default route taking in a value?
You always need to specify the controller and action parameters:
routes.MapRoute
(
"SharedError",
"Shared/Error/{error}",
new { controller = "Shared", action="Error", error = "" }
);
I'm guessing that the reason why using id works for you is because you have the default route still registered, which has id as a parameter and default values for controller and action.
Note, if you still have the default route, make sure you add your route before it, otherwise it will match the other one first.