ASP.NET MVC API路由

Question

I am trying to create a route to an API in my ASP.NET MVC app. Examples of calls to this API look like this:

/MyApp/api/lookup/person?i1=123&i2=test
/MyApp/api/lookup/product?i1=597&i2=1234
/MyApp/api/lookup/order?i1=1&i2=597

The general structure of the route looks like this:

/{AppRoot}/api/lookup/{someKey}?i1={value1}&i2={value2}

I added a route in my WebApiConfig.cs file that looks like this:

config.Routes.MapHttpRoute(
  name: "LookupApi",
  routeTemplate: "api/lookup/{action}",
  defaults: new { controller = "LookupApi", action = "Index" }
);

I then have a controller defined like this:

public class LookupApiController
{
  [HttpGet]
  public async Task<IHttpActionResult> Index()
  {
    return Ok();
  }
}

When I set a breakpoint in the Index action, it is not getting called. I do not understand why. I wish there was an easy way to see what Controller Action was called for a given route and which line of code that mapped to. Either way, how do I resolve this issue of my Lookup action not getting called?

Answer 1

From what you defined routeTemplate: "api/lookup/{action}" , for url like /MyApp/api/lookup/person?i1=123&i2=test , it will take person as action name, and will try to find an action called person in the LookupApiController which doesn't exist.

I am not sure if you want to create those actions to fit your structure or not, a straight forward way to make the example url to hit the Index action is to change your route to:

config.Routes.MapHttpRoute(
  name: "LookupApi",
  routeTemplate: "api/lookup/{someKey}",
  defaults: new { controller = "LookupApi", action = "Index" }
);

In this way the person in your url will no longer represents the action name, and you can grab the value as parameter in the Index action:

public class LookupApiController
{
  [HttpGet]
  public async Task<IHttpActionResult> Index(string someKey)
  {
    //DO something
    return Ok();
  }
}