Web API Routing - api/{controller}/{action}/{id} "dysfunctions" api/{controller}/{id}
Solution 1
The route engine uses the same sequence as you add rules into it. Once it gets the first matched rule, it will stop checking other rules and take this to search for controller and action.
So, you should:
Put your specific rules ahead of your general rules(like default), which means use
RouteTable.Routes.MapHttpRoute
to map "WithActionApi" first, then "DefaultApi".Remove the
defaults: new { id = System.Web.Http.RouteParameter.Optional }
parameter of your "WithActionApi" rule because once id is optional, url like "/api/{part1}/{part2}" will never goes into "DefaultApi".Add an named action to your "DefaultApi" to tell the route engine which action to enter. Otherwise once you have more than one actions in your controller, the engine won't know which one to use and throws "Multiple actions were found that match the request: ...". Then to make it matches your Get method, use an ActionNameAttribute.
So your route should like this:
// Map this rule first
RouteTable.Routes.MapRoute(
"WithActionApi",
"api/{controller}/{action}/{id}"
);
RouteTable.Routes.MapRoute(
"DefaultApi",
"api/{controller}/{id}",
new { action="DefaultAction", id = System.Web.Http.RouteParameter.Optional }
);
And your controller:
[ActionName("DefaultAction")] //Map Action and you can name your method with any text
public string Get(int id)
{
return "object of id id";
}
[HttpGet]
public IEnumerable<string> ByCategoryId(int id)
{
return new string[] { "byCategory1", "byCategory2" };
}
Solution 2
You can solve your problem with help of Attribute routing
Controller
[Route("api/category/{categoryId}")]
public IEnumerable<Order> GetCategoryId(int categoryId) { ... }
URI in jquery
api/category/1
Route Configuration
using System.Web.Http;
namespace WebApplication
{
public static class WebApiConfig
{
public static void Register(HttpConfiguration config)
{
// Web API routes
config.MapHttpAttributeRoutes();
// Other Web API configuration not shown.
}
}
}
and your default routing is working as default convention-based routing
Controller
public string Get(int id)
{
return "object of id id";
}
URI in Jquery
/api/records/1
Route Configuration
public static class WebApiConfig
{
public static void Register(HttpConfiguration config)
{
// Attribute routing.
config.MapHttpAttributeRoutes();
// Convention-based routing.
config.Routes.MapHttpRoute(
name: "DefaultApi",
routeTemplate: "api/{controller}/{id}",
defaults: new { id = RouteParameter.Optional }
);
}
}
Review article for more information Attribute routing and onvention-based routing here & this
Mickael Caruso
Enthusiast Programmer working in mostly C#, the .net Framework, SQL Server, Flex/Actionscript, and (new to) Android.
Updated on August 15, 2020Comments
-
Mickael Caruso over 3 years
I have the default Route in Global.asax:
RouteTable.Routes.MapHttpRoute( name: "DefaultApi", routeTemplate: "api/{controller}/{id}", defaults: new { id = System.Web.Http.RouteParameter.Optional } );
I wanted to be able to target a specific function, so I created another route:
RouteTable.Routes.MapHttpRoute( name: "WithActionApi", routeTemplate: "api/{controller}/{action}/{id}", defaults: new { id = System.Web.Http.RouteParameter.Optional } );
So, in my controller, I have:
public string Get(int id) { return "object of id id"; } [HttpGet] public IEnumerable<string> ByCategoryId(int id) { return new string[] { "byCategory1", "byCategory2" }; }
Calling
.../api/records/bycategoryid/5
will give me what I want. However, calling.../api/records/1
will give me the errorMultiple actions were found that match the request: ...
I understand why that is - the routes just define what URLs are valid, but when it comes to function matching, both
Get(int id)
andByCategoryId(int id)
matchapi/{controller}/{id}
, which is what confuses the framework.What do I need to do to get the default API route to work again, and keep the one with
{action}
? I thought of creating a different controller namedRecordByCategoryIdController
to match the default API route, for which I would request.../api/recordbycategoryid/5
. However, I find that to be a "dirty" (thus unsatisfactory) solution. I've looked for answers on this and no tutorial out there on using a route with{action}
even mentions this issue. -
Mickael Caruso over 11 yearsI tried the advice above and everything works as expected. Thank you very much for that "secret".
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karim over 9 yearsgod answer. but can't we add for all, api/{controller}/{action}/{id} along with api/{controller}/{id} ?
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Deeb over 9 yearsAttribute routing definitly solves the problem. One important point: Prior to Web API 2, the Web API project templates generated code like this: protected void Application_Start() { WebApiConfig.Register(GlobalConfiguration.Configuration); }If attribute routing is enabled, this code will throw an exception. If you upgrade an existing Web API project to use attribute routing, make sure to update this configuration code to the following: protected void Application_Start() { GlobalConfiguration.Configure(WebApiConfig.Register); }
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orad about 9 yearsOn point 2 in your answer, if
id
is optional then URL like/api/{part1}/{part2}
may still go intoDefaultApi
route if no matching action is found forWithActionApi
route. Please correct me if I'm wrong. -
ahsant over 4 yearswhat happens if I want to have api/{controller}/{action} only. without id. If someone else is facing same issue. forget about WebApiConfig. read about Attribute Routing.