How to create ASP.NET MVC controller accepting unlimited amount of parameters from query string - asp.net-mvc

Question

Example of URL
http_//host/url/unlimited/index?first=value1&second=value2...&anyvalidname=somevalue
I want to have one action accepting unknown in advance amount of params with unknown names. Something like this:
public class UnlimitedController : Controller
{
public ActionResult Index(object queryParams)
{
}
//or even better
public ActionResult Index(Dictionary<string, object> queryParams)
{
}
}

Answer 1

You could create a custom model binder that will convert the querystrings into dictionary.
Custom Model Binder
public class CustomModelBinder: IModelBinder
{
public object BindModel(ControllerContext controllerContext, ModelBindingContext bindingContext)
{
var querystrings = controllerContext.HttpContext.Request.QueryString;
return querystrings.Cast<string>()
.Select(s => new { Key = s, Value = querystrings[s] })
.ToDictionary(p => p.Key, p => p.Value);
}
}
Action
public ActionResult Index([ModelBinder(typeof(CustomModelBinder))]
Dictionary<string, string> queryParams)
{
}

Answer 2

In HomeController.cs
public ActionResult Test()
{
Dictionary<string, string> data = new Dictionary<string, string>();
foreach (string index in Request.QueryString.AllKeys)
{
data.Add(index, Request.QueryString[index]);
}
StringBuilder sb = new StringBuilder();
foreach (var element in data)
{
sb.Append(element.Key + ": " + element.Value + "<br />");
}
ViewBag.Data = sb.ToString();
return View();
}
In Test.cshtml
<h2>Test</h2>
#Html.Raw(ViewBag.Data)
Webpage, http://localhost:35268/Home/Test?var1=1&var2=2, shows:
var1: 1
var2: 2

Answer 3

why dont you keep everything you want inside a single query string parameter and get it on server side as string
then parse the string urself and get what ever you want
something like this
http://example.com?a=someVar&b=var1_value1__var2_value2__var3_value3
then at server side just split the string and get the variables and all the values
if you dont want this then what you can do is that
just call the controller through the url and manually get into the Request.QueryString[] collection and you will get all the variables and there values there

Answer 4

Your controller code could be like
public ActionResult MultipleParam(int a, int b, int c)
{
ViewData["Output"] = a + b + c;
return View();
}
Global.asax.cs
public static void RegisterRoutes(RouteCollection routes)
{
routes.IgnoreRoute("{resource}.axd/{*pathInfo}");
routes.MapRoute(
"Parameter",
"{controller}/{action}/{a}/{b}/{c}",
new { controller = "Home", action = "MultipleParam", a = 0, b = 0, c = 0 }
);
}
If the route is {controller}/{action}/{id}/{page}, then /Home/MultipleParam/101/1?showComments=true, then the retrieval mechanism would be:
public ActionResult MultipleParam(string id /* = "101" */, int page /* = 1 */, bool showComments /* = true */) { }

Answer 5

Another possible solution is to create custom Route
public class ParamsEnabledRoute : RouteBase
{
private Route route;
public ParamsEnabledRoute(string url)
{
route = new Route(url, new MvcRouteHandler());
}
public override RouteData GetRouteData(HttpContextBase context)
{
var data = route.GetRouteData(context);
if (data != null)
{
var paramName = (string)data.Values["paramname"] ?? "parameters";
var parameters = context.Request.QueryString.AllKeys.ToDictionary(key => key, key => context.Request.QueryString[key]);
data.Values.Add(paramName, parameters);
return data;
}
return null;
}
public override VirtualPathData GetVirtualPath(RequestContext context, RouteValueDictionary rvd)
{
return route.GetVirtualPath(context, rvd);
}
}
Usage:
public static void RegisterRoutes(RouteCollection routes)
{
routes.IgnoreRoute("{resource}.axd/{*pathInfo}");
routes.Add(new ParamsEnabledRoute("ParamsEnabled/{controller}/{action}/{paramname}"));
}
Controller:
public class HomeController : Controller
{
public ActionResult Test(Dictionary<string, string> parameters)
{
}
}
URL:
http://localhost/ParamsEnabled/Home/Test/parameteres?param1=value1&param2=value2
Route attribute:
public class RouteDataValueAttribute : ActionMethodSelectorAttribute
{
private readonly RouteDataValueAttributeEnum type;
public RouteDataValueAttribute(string valueName)
: this(valueName, RouteDataValueAttributeEnum.Required)
{
}
public RouteDataValueAttribute(string valueName, RouteDataValueAttributeEnum type)
{
this.type = type;
ValueName = valueName;
}
public override bool IsValidForRequest(ControllerContext controllerContext, MethodInfo methodInfo)
{
if (type == RouteDataValueAttributeEnum.Forbidden)
{
return controllerContext.RouteData.Values[ValueName] == null;
}
if (type == RouteDataValueAttributeEnum.Required)
{
return controllerContext.RouteData.Values[ValueName] != null;
}
return false;
}
public string ValueName { get; private set; }
}
public enum RouteDataValueAttributeEnum
{
Required,
Forbidden
}

Answer 6

Just use HttpContext to gather your query string.
using System.Web;
public class UnlimitedController : Controller
{
public ActionResult Index(object queryParams)
{
}
//or even better
public ActionResult Index()
{
NameValueCollection queryString = HttpContext.Request.QueryString;
// Access queryString in the same manner you would any Collection, including a Dictionary.
}
}
The question asked "How to create ASP.NET MVC controller accepting unlimited amount of parameters from query string"? Any controller will accept unlimited amount of parameters as a NamedValueCollection.