I am trying to overload the MVC controllers, how can I overload it properly?
I want to list all companies in my website in a ListCompanies() controller like below
http://localhost:21047/Home/ListCompanies
and I want to add search criteria if user makes a search like below
http://localhost:21047/Home/ListCompanies/sera
"sera" is my search criteria. if search criteria exist, I want to filter my search result according to the search criteria.
here are my controllers
public ActionResult ListCompanies()
{
return View(db.AY_COMPANIES);
}
[ActionName("ListCompaniesFilter")]
public ActionResult ListCompanies(string filter)
{
var filtredCompanies = from c in db.AY_COMPANIES
where c.COMPANY_FULL_NAME.StartsWith(filter)
select c;
return View(filtredCompanies);
}
and here is my ROUTING which behaves not correctly.
public static void RegisterRoutes(RouteCollection routes)
{
routes.IgnoreRoute("{resource}.axd/{*pathInfo}");
routes.MapRoute(
"Default", // Route name
"{controller}/{action}/{id}", // URL with parameters
new { controller = "Home", action = "Index", id = UrlParameter.Optional } // Parameter defaults
);
routes.MapRoute(
"Home", // Route name
"{controller}/{action}/{filter}", // URL with parameters
new { controller = "Home", action = "ListCompanies", filter = UrlParameter.Optional} // Parameter defaults
);
}
My MapRoutes are not correct because it doesnt get the search criteria properly. how can I fix this?
You can't overload in this manner because there is dispatch issue due to two routes on having the same three parts, they are essentially the same.
"{controller}/{action}/{id}"
and
"{controller}/{action}/{filter}"
One way is to collapse the two action methods into one
public ActionResult ListCompanies(string filter)
then if filter is null return the full list else return the filtered list.
I am not fond of this approach.
A better yet simple way to fix this is:
1) remove the second route (the one with the filter)
2) change the signature of the action method from
public ActionResult ListCompanies(string filter)
to
public ActionResult ListCompanies(string id)
allowing the first route to match the parameter on name.
3) Since you can't overload methods you'll need to use your ActionName when requesting the filtered result,
http://localhost:21047/Home/ListCompaniesFilter/sera
First these routes are exactly the same:
routes.MapRoute(
"Default", // Route name
"{controller}/{action}/{id}", // URL with parameters
new { controller = "Home", action = "Index",
id = UrlParameter.Optional } // Parameter defaults
);
routes.MapRoute(
"Home", // Route name
"{controller}/{action}/{filter}", // URL with parameters
new { controller = "Home", action = "ListCompanies",
filter = UrlParameter.Optional} // Parameter defaults
);
They are exactly the same because the number of parameters exactly match (what you name parameters nor the parameter type does not change the signature of the http request method).
There are few different ways to make this work. You could write a MapRoute Constraint for Default that would prevent it from working if the controller/action/id matched a specific set of criteria. Probably not the best course of action.
Since
http://localhost:21047/Home/ListCompanies
http://localhost:21047/Home/ListCompanies/sera
http://localhost:21047/Home/ListCompanies/text
http://localhost:21047/Home/ListCompanies/search
are programmatically the same request with {id} having a null value for your method ListCompanies() I would probably write it like:
public ActionResult ListCompanies(string id)
{
var query = db.AY_COMPANIES;
if (!string.IsNullOrWhiteSpace(id))
{
query.Where(c => c.COMPANY_FULL_NAME.StartsWith(id))
}
var model = query.ToList();
return View(model);
}
And remove your "Home" MapRoute, it won't be needed.
What happens if you have only one action with an optional parameter? Something like as the following:
public ActionResult ListCompanies(string filter = null)
{
var filteredCompanies = string.IsNullOrEmpty(filter)
? db.AY_COMPANIES
: from c in db.AY_COMPANIES
where c.COMPANY_FULL_NAME.StartsWith(filter)
select c;
return View(filteredCompanies);
}
Related
I am using
'routes.MapRoute'
to take one parameter without calling the action name. it works fine, but now my problem is whenever I wanted to use any other action form the same controller it's always calling the same action that is described on the 'routes.MapRoute'.
My ajax calling for all other action has GET type. but still, it's calling the same action that is described in the routes.MapRoute.
//This is my custom route.
routes.MapRoute(
"kuenstler",
"kuenstler/{name}",
new { controller = "kuenstler", action = "Index" }
);
//my default route
routes.MapRoute(
name: "Default",
url: "{controller}/{action}/{id}",
defaults: new { controller = "Site", action = "Index", id
=
UrlParameter.Optional }
);
The first route will be called from a link attribute from another page so I need to get the name from there but without the action name.
link
action that needs to get the name from the calling.
public ActionResult Index(string name)
{
return View();
}
[HttpGet]
public ActionResult GetKuenstlerGalleryData(int? artistId, string
direction)
{
/// some code
}
Every time I am clicking the link
//localhost:50519/Kuenstler/firstname-lastname.
I am getting the name in my Index. Then I am calling the second action from javascript with GET type. But every time it's coming in the Index with the calling action name as parameter.
But every time it's coming in the Index with the calling action name as parameter.
Of course it does, your requests path perfectly fits the kuenstler route template.
You can map specific route for GetKuenstlerGalleryData action right before 'kuenstler' one. Ex.
routes.MapRoute(
"kuenstler-gallery-data",
"kuenstler/GetKuenstlerGalleryData",
new { controller = "kuenstler", action = "GetKuenstlerGalleryData" }
);
routes.MapRoute(
"kuenstler",
"kuenstler/{name}",
new { controller = "kuenstler", action = "Index" }
);
or use separate template, ex.
routes.MapRoute(
"kuenstler-gallery-data",
"kuenstler-gallery-data",
new { controller = "kuenstler", action = "GetKuenstlerGalleryData" }
);
or even use attribute routing
I am new in c# mvc, and I am trying to make a route with multiple parameters that looks like this:
controller/action/parameterOne/parameterTwo
but in some cases I'm gonna just use one of them so the route will look like this:
controller/action/parameterOne
here is my RouteConfig.cs
public static void RegisterRoutes(RouteCollection routes)
{
routes.IgnoreRoute("{resource}.axd/{*pathInfo}");
routes.MapRoute(
name: "Default",
url: "{controller}/{action}/{id}",
defaults: new { controller = "Home", action = "Index", id = UrlParameter.Optional }
);
routes.MapRoute(
name:"Default2",
url: "{controller}/{action}/{category}/{id}",
defaults: new { controller = "Home", action = "Index", category = UrlParameter.Optional, id = UrlParameter.Optional }
);
}
now in my controller's action I need to check if there is only one parameter or two so I can return a different view for each condition, here is the controller:
[HttpGet]
public ActionResult someAction(string category, string id)
{
if (String.IsNullOrWhiteSpace(id))
{
return View("viewOne");
}
else
{
return View("ViewTwo");
}
}
the problem is that the if statement is not full working? because if the conditoin is this: String.IsNullOrWhiteSpace(id)
and if I write controller/action/parameterOne this return the ViewOne
but if I write controller/action/parameterOne/parameterTwo also return the ViewOne
but now if a invert the condition and I write !String.IsNullOrWhiteSpace(id) both urls return ViewTwo.
So does any one have any idea why is that happening?
Do you have any objection to only using the default route? The only drawback that comes to mind is if you really want your url to look a certain way in which case you may need to define multiple routes as youre trying to do. However, the following should work with only the default route:
//note controller actions will default to HttpGet if no data annotation is explicitly supplied. Also, action names generally begin uppercase by convention
public ActionResult SomeAction(string category, string id = null)
{
if (String.IsNullOrWhiteSpace(id))
{
return View("viewOne");
}
else
{
return View("ViewTwo");
}
}
the various requests you mentioned would look like:
www.myhost.com/controller/someaction?category=parameterOne&id=parameterTwo
or
www.myhost.com/controller/someaction?category=parameterOne
I want to redirect to an action in other Controller but it doesn't work
here's my code in ProductManagerController:
[HttpPost]
public ActionResult RedirectToImages(int id)
{
return RedirectToAction("Index","ProductImageManeger", new { id=id });
}
and this in my ProductImageManagerController:
[HttpGet]
public ViewResult Index(int id)
{
return View("Index",_db.ProductImages.Where(rs=>rs.ProductId == id).ToList());
}
It redirect to ProductImageManager/Index without parameter very well(no error) but with above code i get this:
The parameters dictionary contains a null entry for
parameter 'ID' of non-nullable type 'System.Int32' for method
'System.Web.Mvc.ViewResult Index(Int32)' in
'...Controllers.ProductImageManagerController'.
An optional parameter must be a reference type, a nullable type, or be
declared as an optional parameter. Parameter name: parameters
This error is very non-descriptive but the key here is that 'ID' is in uppercase. This indicates that the route has not been correctly set up. To let the application handle URLs with an id, you need to make sure that there's at least one route configured for it. You do this in the RouteConfig.cs located in the App_Start folder. The most common is to add the id as an optional parameter to the default route.
public static void RegisterRoutes(RouteCollection routes)
{
//adding the {id} and setting is as optional so that you do not need to use it for every action
routes.MapRoute(
name: "Default",
url: "{controller}/{action}/{id}",
defaults: new { controller = "Home", action = "Index", id = UrlParameter.Optional }
);
}
Now you should be able to redirect to your controller the way you have set it up.
[HttpPost]
public ActionResult RedirectToImages(int id)
{
return RedirectToAction("Index","ProductImageManager", new { id });
//if the action is in the same controller, you can omit the controller:
//RedirectToAction("Index", new { id });
}
In one or two occassions way back I ran into some issues by normal redirect and had to resort to doing it by passing a RouteValueDictionary. More information on RedirectToAction with parameter
return RedirectToAction("Index", new RouteValueDictionary(
new { controller = "ProductImageManager", action = "Index", id = id } )
);
If you get a very similar error but in lowercase 'id', this is usually because the route expects an id parameter that has not been provided (calling a route without the id /ProductImageManager/Index). See this so question for more information.
This should work!
[HttpPost]
public ActionResult RedirectToImages(int id)
{
return RedirectToAction("Index", "ProductImageManeger", new { id = id });
}
[HttpGet]
public ViewResult Index(int id)
{
return View(_db.ProductImages.Where(rs => rs.ProductId == id).ToList());
}
Notice that you don't have to pass the name of view if you are returning the same view as implemented by the action.
Your view should inherit the model as this:
#model <Your class name>
You can then access your model in view as:
#Model.<property_name>
Try this,
return RedirectToAction("ActionEventName", "Controller", new { ID = model.ID, SiteID = model.SiteID });
Here i mention you are pass multiple values or model also.
That's why here i mention that.
return RedirectToAction("ProductImageManager","Index", new { id=id });
Here is an invalid parameters order, should be an action first
AND
ensure your routing table is correct
I am creating a blog engine, and I need a custom route, like this:
localhost/blogname/posts/1
Where blogname should be handled by a BlogsController, and posts will be an action.
How would I define such a route?
I don't think you need to define {controller} in your Url if you define it as a constraint. I think this should work:
routes.MapRoute("Default",
"{action}/{id}",
new { controller = "Blogs", action = "Posts" },
new { controller = "Blogs"});
It might cause problems with other routes though, I'm not sure. If it doesn't work, David's answer of http://site.com/blogs/posts/id is the best way to go.
This feels like a weird approach. If you use the default routing in ASP.NET MVC, you would need one controller class per blog--not something you can easily create on the fly.
If you use the classname BlogsController, then the default routing would work for URLs of the form:
/Blogs/SomeAction/123
Maybe this is what you're looking for:
public class BlogsController : Controller
{
public ActionResult List()
{
return View(GetPostsOrSomething());
}
public ActionResult Posts(int id)
{
return View(new BlogViewModel(id));
}
[HttpPost]
public ActionResult Comment(int id, string comment)
{
// do comment
}
}
And your routing would need to look like this:
routes.MapRoute(
"Blogs", // Route name
"{blog}/{action}/{id}", // URL with parameters
new { controller = "Blogs", action = "List", id = UrlParameter.Optional }
);
Note
Bear in mind, this would match default style URLs, and everything might be routed to your BlogsController. Maybe you could consider a regular expression for the {blog} part of the pattern:
routes.MapRoute(
"Blogs", // Route name
"{blog}/{action}/{id}", // URL with parameters
new { controller = "Blogs", action = "List", id = UrlParameter.Optional },
new { blog = "(blogname1|blogname2|blogname3|etc)" }
);
But, this isn't very flexible either. Any time you added a blog to your site, this regular expression would require an update. I would probably reconsider your URL structure--something similar to the default style.
Something like this
routes.MapRoute(
"Blogs", // Route name
"{blogname}/{action}/{id}", // URL with parameters
new { controller = "Blog", action = "Posts", id = UrlParameter.Optional } // Parameter defaults
);
would work, meaning you could have your blog controller like this:
public class BlogController : Controller
{
public ActionResult Posts(string blogname, int id)
{
... get posts based on blog name and id and return view...
}
}
but then if you want a url like localhost/admin/dostuff/1 to go to an admin controller, how will MVC know that you don't just mean a 'blogname' called 'admin'?
You would need to do something like the regex matching that David suggests, or else specifically add a route for any other controllers you have before you add the Blog route
e.g.
routes.MapRoute(
"Admin Controller Routes", // Route name
"admin/{action}/{id}", // URL with parameters
new { controller = "Admin", id = UrlParameter.Optional } // Parameter defaults
);
routes.MapRoute(
"Account Controller Routes", // Route name
"account/{action}/{id}", // URL with parameters
new { controller = "Account", id = UrlParameter.Optional } // Parameter defaults
);
... etc - one for each controller ...
I found this approach to be best for my needs. Very simple, goal is to have the title of the blog as the parameter but also the URL (I didn't want a ? to set a parameter value, I have been told it is not helping SEO. Goal is MYURL.com/blog/my-blog-title
ASP.NET MVC
add to your RouteConfig.cs file
routes.MapMvcAttributeRoutes();
routes.MapRoute(
name: "Blog",
url: "blog/{title}",
defaults: new { controller = "Blog", action = "GetBlog" },
constraints: new { title = #"[\w\-]*" }
);
Add a Controller and call it Blog and then add the following Action to that Controller
[Route("blog/{title}")]
public ActionResult GetBlog(string title)
{
// do what ever code you need to do here to get the blog from the title and pass a model to the view using return View(MyBlogObject)
return View();
}
Using the default route provided, I'm forced to name my parameters "id". That's fine for a lot of my Controller Actions, but I want to use some better variable naming in certain places. Is there some sort of attribute I can use so that I can have more meaningful variable names in my action signatures?
// Default Route:
routes.MapRoute(
"Default", // Route name
"{controller}/{action}/{id}", // URL with parameters
new { controller = "Home", action = "Index", id = "" } // Parameter defaults
);
// Action Signature:
public ActionResult ByAlias(string alias)
{
// Because the route specifies "id" and this action takes an "alias", nothing is bound
}
Use the [Bind] attribute:
public ActionResult ByAlias([Bind(Prefix = "id")] string alias) {
// your code here
}
This still works, your query string will just look like "/Controller/ByAlias?alias=something".
You can customize the routes with whatever identifiers you like..
routes.MapRoute(
"Default", // Route name
"{controller}/{action}/{alias}", // URL with parameters
new { controller = "Home", action = "Index", alias = "" } // Parameter defaults
);
Edit: Here's an overview from the ASP.NET site
Just because your route uses the name "id" for the ID variable doesn't mean that you have to use the same name in your controller action methods.
For example, given this controller method...
public Controller MailerController
{
public ActionResult Details(int mailerID)
{
...
return View(new { id = mailerID });
}
}
...and this action method call from the view...
<%= Html.ActionLink("More Info", "Details", new { mailerID = 7 }) %>
...you can use whatever naming convention you wish for the ID parameter in your controller action methods. All you need to do is resolve the new name to the default, whether it's "id", "alias", or whatever.
The above example should resolve to :
More Info