CODEWITHSUNDEEP
c#asp.net-web-apiasp.net-web-api-routing
Sander
Sander

Reputation: 73

Routing with optional parameter in web-api

Using web-api i go to /api/cat/orders/

I specified the following routes and controller methods. I expected that the "ApiRouteWithCategoryAndExtId" route and the "GetMessageByCategoryExtId" method would be used since I made "extid" optional. But it is using the default Get method.

(/api/cat/orders/id18 uses GetMessageByCategoryExtId, but then extid is not optional)

What am I doing wrong?

Routes: 

config.Routes.MapHttpRoute(
    name: "ApiRouteUniqueId",
    routeTemplate: "api/def/{id}",
    defaults: new { id = RouteParameter.Optional, controller = "Default" }
);

config.Routes.MapHttpRoute(
    name: "ApiRouteWithCategoryAndExtId",
    routeTemplate: "api/cat/{category}/{extid}",
    defaults: new { extid = RouteParameter.Optional, controller = "Default"}
);

Controller: 

public string Get()

public HttpResponseMessage GetMessageById(int id)

public HttpResponseMessage GetMessageByCategoryExtId(
    string category, string extid)

Upvotes: 1

Views: 5657

Answers (1)

Kiran
Kiran

Reputation: 57949

Here you would need to specify a default value for extid:

public HttpResponseMessage GetMessageByCategoryExtId(
    string category, string extid **= null**)

if the above default value is not specified, webapi tries to do a strict matching of an action's parameters with available values(via route parameters or query string values) and since here your url here /api/cat/orders/ does not have a value for 'extid', it isn't present in the route values and hence webapi cannot match to GetMessageByCategoryExtId.

Upvotes: 1

Related Questions