ASP.NET Core Web API : route by query parameter

Question

I am coming from a heavy Java/Spring background and trying to transition some knowledge over to ASP.NET Core 6.

In Spring, on a RestController , I am able to route the request based on the presence of a query parameter.

So a HttpRequest with the uri: /students?firstName=Kevin can be routed to a different controller method than a HttpRequest with the uri: /students .

In ASP.NET Core 6, I am unable to determine if the equivalent is possible after working through some examples and reading the documentation for Web API.

Here is what I am trying to achieve, is this possible using two methods and routing configuration that will discern which controller method to invoke based on the query parameter?

 [ApiController]
 [Route("Students")]
 public class StudentHomeProfileController : ControllerBase
 {
    [HttpGet] //Route here when no parameters provided
    public async Task<ActionResult<IEnumerable<Student>>> GetStudentAsync()
    {
        /* Code omitted */
    }

    [HttpGet] //Route here when firstName query param provided
    public async Task<ActionResult<IEnumerable<Student>>> SearchStudentAsync([FromQuery] string firstName)
    {
        /* Code omitted */
    }
 }

Answer 1

You are trying to differentiate API calls using query params . this is not the way to do this. if you want to separate the calls you should probably use path params instead.

Read more about Routing in ASP.NET Core - https://docs.microsoft.com/en-us/aspnet/core/fundamentals/routing?view=aspnetcore-6.0

Answer 2

I think you are looking for something like this, you need to specify the parameter in the " HttpGet " attribute

https://docs.microsoft.com/en-us/aspnet/core/mvc/controllers/routing?view=aspnetcore-6.0#attribute-routing-with-http-verb-attributes

[Route("api/[controller]")]
[ApiController]
public class Test2Controller : ControllerBase
{
    [HttpGet]   // GET /api/test2
    public IActionResult ListProducts()
    {
        return ControllerContext.MyDisplayRouteInfo();
    }

    [HttpGet("{id}")]   // GET /api/test2/xyz
    public IActionResult GetProduct(string id)
    {
       return ControllerContext.MyDisplayRouteInfo(id);
    }

    [HttpGet("int/{id:int}")] // GET /api/test2/int/3
    public IActionResult GetIntProduct(int id)
    {
        return ControllerContext.MyDisplayRouteInfo(id);
    }

    [HttpGet("int2/{id}")]  // GET /api/test2/int2/3
    public IActionResult GetInt2Product(int id)
    {
        return ControllerContext.MyDisplayRouteInfo(id);
    }
}