Post Action method overload with same route name in ASP.Net Web API Controller

Question

Is it possible to have two actions with same route name and same method but different parameter? I have tried this:

[HttpPost]
[Route("gstr4")]
public HttpResponseMessage SubmitGSTR4([FromBody] RequestPayloadWithoutSign requestPayload)
{ }

[HttpPost]
[Route("gstr4")]
public HttpResponseMessage FileGSTR4([FromBody] RequestPayloadWithSign requestPayload)
{ }

I received a Status Code of 500 (InternalServerError) and here is raw response:

{"Message":"An error has occurred.","ExceptionMessage":"Multiple actions were found that match the request: \r\nFileGSTR4 on type APIPortal.Controllers.GSTR4Controller\r\nSubmitGSTR4 on type APIPortal.Controllers.GSTR4Controller","ExceptionType":"System.InvalidOperationException","StackTrace":"   at System.Web.Http.Controllers.ApiControllerActionSelector.ActionSelectorCacheItem.SelectAction(HttpControllerContext controllerContext)\r\n   at System.Web.Http.Controllers.ApiControllerActionSelector.SelectAction(HttpControllerContext controllerContext)\r\n   at System.Web.Http.ApiController.ExecuteAsync(HttpControllerContext controllerContext, CancellationToken cancellationToken)\r\n   at System.Web.Http.Dispatcher.HttpControllerDispatcher.<SendAsync>d__1.MoveNext()"}

No, its not possible. You can have identical `route` with different `http` `state`, ie. (`get`, `post`). But that will not possible to have two `GET` with same `route`. — Karan, Jun 01 '20 at 07:28
Why dont you just create on method and then check "the sign" — Daniaal, Jun 01 '20 at 09:46

Jacek · Answer 1 · 2022-01-04T22:11:34.050

It's not possible to have many actions with the same route and the same HTTP verb.

What you could do is to have a single action which accepts a model of a base class (possibly an abstract class) and a custom resolver.

Example:

public abstract class RequestPayload 
{
}

public class RequestPayloadWithoutSign : RequestPayload
{
}

public class RequestPayloadWithSign : RequestPayload
{
   public string Sign { get; set; }
}

public class MyController
{
    [HttpPost]
    [Route("gstr4")]
    public HttpResponseMessage SubmitGSTR4([FromBody] RequestPayload payload)
    {
        switch(payload)
        {
            case RequestPayloadWithoutSign a:
                // handle RequestPayloadWithoutSign
                break;
            case RequestPayloadWithSign b:
                // handle RequestPayloadWithSign
                break;
        }
    }
}

And, if you're using JSON mediatype for transmitting payloads, a custom JSON resolver attached to your JSON deserializer. Here's an example for Newtonsoft.Json:

class HolderConverter : JsonConverter
{
    public override bool CanConvert(Type objectType)
    {
        return objectType == typeof(RequestPayload);
    }

    public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
    {
        JObject jo = JObject.Load(reader);
        if (jo.ContainsKey("sign"))
        {
            return new RequestPayloadWithSign
            {
                Sign = (string) jo["sign"]
            };
        }

        return new RequestPayloadWithoutSign();
    }

    public override bool CanWrite
    {
        get { return false; }
    }

    public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)
    {
        throw new NotImplementedException();
    }
}

Now add the converter to serializer settings or mark your RequestPayload class definition with [JsonConverter(typeof(RequestPayload))] attribute and it will start converting JSONs to either RequestPayloadWithSign or RequestPayloadWithoutSign types.

score 0 · Answer 2 · answered Jun 01 '20 at 07:34

0

It's not possible for the same method type as http Get for multiple methods. You should have a different route

answered Jun 01 '20 at 07:34

Vivek Nuna

25,472
25
109
197

There has to be some or other way. – Rithik Banerjee Jun 01 '20 at 11:03
It's not possible wit the same verb – Vivek Nuna Jun 01 '20 at 11:05

score 0 · Answer 3 · edited Jun 01 '20 at 11:17

0

It is only possible with different HTTP verbs. Otherwise, you have to define different routes.

https://learn.microsoft.com/en-us/aspnet/web-api/overview/web-api-routing-and-actions/routing-in-aspnet-web-api

edited Jun 01 '20 at 11:17

Dilberted

1,172
10
23

answered Jun 01 '20 at 09:28

Laky

29
2

if the request payload is of model A then it should hit action with parameter A and if the request payload is of model B then it should hit action with parameter B. Possible? – Rithik Banerjee Jun 01 '20 at 10:40
I don't think you can do it with custom objects. One way to trick it is, to have one method and then delegate based on the payload. Check the following link:-https://stackoverflow.com/questions/14353466/overload-web-api-action-method-based-on-parameter-type – Laky Jun 02 '20 at 07:49

Post Action method overload with same route name in ASP.Net Web API Controller

3 Answers3