The new ASP.NET routing is great for simple path style URL's but if you want to use a url such as:
http://example.com/items/search.xhtml?term=Text+to+find&page=2
Do you have to use a catch all parameter with a validation?
You can match querystring parameters with routes as well, if you want to just capture everything you need to add a parameter like so:
{*contentUrl}
Which will populate the rest of the url into that variable.
Any view data items that are not listed in the route are automatically mapped to the querystring, so if you map "items/search.xhtml" to an action:
Search(string term, int page)
Then you should get the results you are looking for.
I was also having trouble passing an encoded URL to a route as a route parameter.
You can't use url encoded chars in a URL, but you can in a query string.
Therefore I needed my route to also have a query string element to it.
Say I have a route:
MapPageRoute("myroute", "myroute/{x}", "~/routehander.aspx")
But I want it in the form of:
http://mywebsite.com/myroute/{x}?url=myurl
We can do this:
Dim x as integer = 12
Dim rvd As New Routing.RouteValueDictionary
rvd.Add("x", x)
rvd.Add("url", Server.UrlEncode("/default.aspx"))
HttpContext.Current.ApplicationInstance.Response.RedirectToRoutePermanent("myroute", rvd)
This would redirect us to the following url:
http://mywebsite.com/myroute/12?url=%252fdefault.aspx
You can still use Request.QueryString["some_value"];
Related
I'm trying to pass a list of URL's with Id attributes from a controller to a view.
I can pass a <a href=...> link back but I don't think writing a 'localhost' absolute path is a clean way of approaching this. I cant pass an ActionLink back as it returns the full string. Is ther a simple solution to this problem? Thanks in advance.
Using this overload of the UrlHelper.Action() method and Request object you can get a complete URL including the route parameters such as IDs and the actual hostname of the application.
string url = Url.Action("action", "controller",
new System.Web.Routing.RouteValueDictionary(new { id = id }),
"http", Request.Url.Host);
UrlHelper is available in the controller via its Url property.
You can then pass such URL into your view.
It is also possible to use UrlHelper directly inside your view to create URLs for controller actions. Depends if you really need to create them inside the controller.
Edit in response to comments:
Wherever you need to place the URLs, this "URL builder" you are looking for is still the UrlHelper. You just need to pass it (or the generated URLs) where you need it, being it inside the controller, view or custom helper.
To get the links inside the unsorted list HTML structure you mention, you need to put anchors inside the list items like this:
<ul>
<li>Link</li>
...
</ul>
Then again you just need to get the URLs from somewhere and that would be from UrlHelper.
Simple and easy.
text
the route id = the parameter that is going to be inserted into your method.
eg.
function Details(int id) {
//id has the value of my_var_id
}
Some MVC sites have querystring params appended to the route Url (of which I noticed StackOverflow does), such as:
https://stackoverflow.com/questions/tagged/java?page=9802&sort=newest&pagesize=15
What are the advantages of having the parameters as more conventional ?querystring params, rather than /param/values/ ?
Also, how are these params appended to routes that have been set up? I'm familiar with setting up mvc routes with params like "users/details/{id}" etc. but don't know how to configure routes for use with 1 or more ?params as per the example url above?
Query string parameters are useful when you have multiple optional parameters and don't want to include default values for non-specified parameters just to satisfy a path.
And you don't have to do anything special to include these parameters in a rendered URL.
Take the following route for example:
routes.MapRoute
(
"QuestionsTagged",
"questions/tagged/{tag}",
new { controller = "Questions", action = "Tagged" }
);
If you render a link to that route using:
Url.RouteUrl
(
"QuestionsTagged",
new
{
tag = "java",
page = 9802,
sort = "newest",
pagesize = 15
}
)
...then the routing engine is smart enough to see that the route contains a parameter named tag and that the passed route values object also has something named tag so it uses that value in the route.
Any provided route values that don't have corresponding parameters in the route (page, sort and pagesize in this case) get tacked on as query string parameters. So the Url.RouteUrl call above would return /questions/tagged/java?page=9802&sort=newest&pagesize=15.
And your action method can explicitly list these parameters in its signature (promotes readability and maintainability) or you can access them via Request.QueryString.
public class QuestionsController : Controller
{
// I can explicitly list the parameters in my signature and let routing do
// its magic, like this...
public ViewResult Tagged(string tag, int? page, int? pagesize)
{
// ...or I can grab parameters like this:
string sort = Request.QueryString["sort"];
return View();
}
}
Note that the parameters to the action method do not have to match the parameters specified in the route. (In the route, I only specified tag, but the action method's signature lists tag, page, and pagesize.) However, any parameter of the action method that is not also a parameter of the route must be a reference or nullable type.
I've normally seen paging and filtering data be passed as querystring parameters since it gives information to the user in the URI. It is also normally harmless if a user alters this data since it will just filter the data you see on the page. Any sensitive data is normally posted so as it is not as easily seen or modified, but I would argue to keep your URI's clean and use quesrystrings as little as possible.
You don't need to do anything special when specifying routes to be able to handle quesrystrings. They will just be extra data that is passed to your action. On your action you will need to do some work to handle the data though. Using your querystring above you will have to specify the querystring names as the parameter names and then whatever datatype you are expecting.
public ActionResult Index (int page, string sort, int pagesize)
In this example, page will be the value of 9802, sort will be "newest" and pagesize will be 15.
I have a simple create action to receive post form data, save to db and redirect to list view.
The problem is, after redirecttoaction result excutes, the url on my browser lost the action section. Which it should be "http://{hotsname}/Product/List" but comes out as "http://{hotsname}/Product/".
Below is my code:
[HttpPost]
public ActionResult Create(VEmployee model, FormCollection fc)
{
var facility = FacilityFactory.GetEmployeeFacility();
var avatar = Request.Files["Avatar"].InputStream;
var newModel = facility.Save(model, avatar);
return RedirectToAction("List");
}
The page can correctly render list view content, but since some links in this view page use relative url, the functions are interrupted. I am now using return Redirect("/Employee/List") to force the url. But I just wonder why the action name is missing. I use MVC3 and .Net framwork 4.
I am new to ASP.Net MVC, thanks for help.
Your route table definitely says that "List" action is default, so when you redirect to it as RedirectToAction("List") - routing ommits the action because it is default.
Now if you remove the default value from your routes - RedirectToAction will produce a correct (for your case) Url, but you'll have to double check elsewhere that you are not relying on List being a default action.
Well, Chris,
If you get the right content on http://{hotsname}/Product/ then it seems that routing make that URL point to List either indirectly (using pattern like {controller}/{action}) and something wrong happens when resolving URL from route or {action} parameter is just set wth default value List. Both URLs can point to the same action but the routing engine somehow takes the route without explicit action name.
You should check:
Order in which you define your routes
How many routes can possibly lead to EmployeeController.List()
Which one of those routes has the most priority
Default values for your routes
Just make the route with explicit values: employee/list to point to your List action and make sure that is the route to select when generating links (it should be most specific route if possible).
It would be nice if you provide your routes mappings here.
but since some links in this view
page use relative url, the functions
are interrupted.
Why do you make it that way? Why not generate all the links through routing engine?
When using the overload RedirectToAction("Action") you need to be specifying an action that is in the same controller. Since you are calling an action in a different controller, you need to specify the action with the alternate overload e.g. RedirectToAction("List", "Employee").
Due to factors outside my control, I need to handle urls like this:
http://www.bob.com/dosomething.asp?val=42
I would like to route them to a specific controller/action with the val already parsed and bound (i.e. an argument to the action).
Ideally my action would look like this:
ActionResult BackwardCompatibleAction(int val)
I found this question: ASP.Net MVC routing legacy URLs passing querystring Ids to controller actions but the redirects are not acceptable.
I have tried routes that parse the query string portion but any route with a question mark is invalid.
I have been able to route the request with this:
routes.MapRoute(
"dosomething.asp Backward compatibility",
"{dosomething}.asp",
new { controller = "MyController", action = "BackwardCompatibleAction"}
);
However, from there the only way to get to the value of val=? is via Request.QueryString. While I could parse the query string inside the controller it would make testing the action more difficult and I would prefer not to have that dependency.
I feel like there is something I can do with the routing, but I don't know what it is. Any help would be very appreciated.
The parameter val within your BackwardCompatibleAction method should be automatically populated with the query string value. Routes are not meant to deal with query strings. The solution you listed in your question looks right to me. Have you tried it to see what happens?
This would also work for your route. Since you are specifying both the controller and the action, you don't need the curly brace parameter.
routes.MapRoute(
"dosomething.asp Backward compatibility",
"dosomething.asp",
new { controller = "MyController", action = "BackwardCompatibleAction"}
);
If you need to parametrize the action name, then something like this should work:
routes.MapRoute(
"dosomething.asp Backward compatibility",
"{action}.asp",
new { controller = "MyController" }
);
That would give you a more generic route that could match multiple different .asp page urls into Action methods.
http://www.bob.com/dosomething.asp?val=42
would route to MyController.dosomething(int val)
and http://www.bob.com/dosomethingelse.asp?val=42
would route to MyController.dosomethingelse(int val)
I have a page routed like /Comments/Search/3 where i search and display all the comments of the thread "3".
I'm adding a sort function (by date, author etc). What is the best way to handle it? /Comments/Search/3/Sort/Author or /Comments/Search/3?sort=author ?
How do I automatically handle the querystring sort=author as a parameter in MVC?
Thanks
I prefer: /Comments/Search/3?sort=author. The querystring is a good place to pass in programmatic parameters, especially if the parameter (like in this case) is not important for SEO purposes. If the parameter had some semantic meaning as a search term, the first URL would be better.
In a controller method you can use something like this:
public ActionResult Search(int id, string sort)
ASP.NET MVC will automatically wire up querystring values to the parameters of your method.
Use the following route
routes.MapRoute(
"Default", // Route name
"{controller}/{action}/{id}", // URL with parameters
new { controller = "Comments", action = "Search", id = "" } // Parameter defaults
);
/Comments/Search/3?sort=author will call Search(3, "author")
/Comments/Search/3 will call Search(3, null)
Keep in mind that id is mandatory so this url will fail:
/Comments/Search
ASP.NET MVC will handle that automatically in the query string case. You just add a string sort parameter to your action.
Which is better? Personally, I use the path to control the contents being displayed and querystring to control the presentation (how it's displayed, formatted, ...). So, for sorting, I'd go with the querystring method. But I don't think there's a technical disadvantage in either approach.
Your best bet is to add a routing rule to handle it. There's a handy article on it here:
http://aspalliance.com/1525_ASPNET_MVC_Framework_Part_2_URL_Routing.2
Then your URL would read /Comments/Search/3/Sort/Author