Create route to webapi method with parameters via querystring

Question

I have the following route in class WebApiConfig of a project Aspnet Wepapi

        config.Routes.MapHttpRoute(
            name: "DefaultApi",
            routeTemplate: "{controller}/{action}/{id}"
        );

Edited: Using @Gabrielcoletta’s reply: The Route was the way it is below, and now the url works http://localhost:62027/Pedidos/Todos?pagina=1&filtro=117 but does not work the following url http://localhost:62027/Pedidos/Todos?filtro=117, only works when both parameters are passed in querystring.

        config.Routes.MapHttpRoute(
            name: "DefaultApi",
            routeTemplate: "{controller}/{action}/{id}",
            defaults: new { id = RouteParameter.Optional }
        );

What works properly for the URL and methods below:

[HttpGet]
[ResponseType(typeof(Pedido))]
public async Task<IHttpActionResult> Detalhes(int id)

http://localhost:62027/Pedidos/Detalhes/104

But for the URL and method below does not work

[HttpGet]
[ResponseType(typeof(IPagedList<Pedido>))]
public async Task<IHttpActionResult> Todos(string filtro, string pagina)

http://localhost:62027/Pedidos/Todos?filtro=s&pagina=1
http://localhost:62027/Pedidos/Todos

Being displayed the following message:

I have another project Aspnet MVC which has the same route and works properly, why does the Webapi not work? which is the correct way?

• Webapi project has only one route and a single route file

Answer 1

It is not finding because the {id} of its route is not optional, so all its route has to have a value for {id} or it will not find route.

Set your route like this and it will work:

config.Routes.MapHttpRoute(
    name: "DefaultApi",
    routeTemplate: "{controller}/{action}/{id}",
    defaults: new { id = UrlParameter.Optional }
);

For the url without the page value to work you have to put a default value to page:

[HttpGet]
[ResponseType(typeof(IPagedList<Pedido>))]
public async Task<IHttpActionResult> Todos(string filtro, string pagina = "")

Or you will have to overload the All method with only one parameter.

Answer 2

You are passing the wrong parameter when calling the action. In the error message you are page=1 and the action is waiting for the variable with the name pagina.