Route to allow a parameter from both query string and default {id} template

问题

I have an action in my ASP.Net Core WebAPI Controller which takes one parameter. I'm trying to configure it to be able to call it in following forms:

api/{controller}/{action}/{id}
api/{controller}/{action}?id={id}

I can't seem to get the routing right, as I can only make one form to be recognized. The (simplified) action signature looks like this: public ActionResult<string> Get(Guid id). These are the routes I've tried:

• [HttpGet("Get")] -- mapped to api/MyController/Get?id=...
• [HttpGet("Get/{id}")] -- mapped to api/MyController/Get/...
• both of them -- mapped to api/MyController/Get/...

How can I configure my action to be called using both URL forms?

回答1:

if you want to use route templates you can provide one in Startup.cs Configure Method Like This:

app.UseMvc(o =>
        {
            o.MapRoute("main", "{controller}/{action}/{id?}");
        });

now you can use both of request addresses.

If you want to use the attribute routing you can use the same way:

[HttpGet("Get/{id?}")]
public async ValueTask<IActionResult> Get(
         Guid id)
    {

        return Ok(id);
    }

回答2:

Make the parameter optional

[Route("api/MyController")]
public class MyController: Controller {

    //GET api/MyController/Get
    //GET api/MyController/Get/{285A477F-22A7-4691-AA51-08247FB93F7E}
    //GET api/MyController/Get?id={285A477F-22A7-4691-AA51-08247FB93F7E}
    [HttpGet("Get/{id:guid?}"
    public ActionResult<string> Get(Guid? id) {

        if(id == null)
            return BadRequest();

        //...
    }    
}

This however means that you would need to do some validation of the parameter in the action to account for the fact that it can be passed in as null because of the action being able to accept api/MyController/Get on its own.

Reference Routing to controller actions in ASP.NET Core

来源：https://stackoverflow.com/questions/51797617/route-to-allow-a-parameter-from-both-query-string-and-default-id-template