Passing enum value as parameter .net core - asp.net-core

Question

I have a controller (ResponseResourceController) which Index Action is supposed to receive as parameter int and in the Index action - Parse enum value from Tempdata. Then this action redirects to another action with this two parameters.
public class ResponseResourceController : Controller
{
public async Task<IActionResult> Index(
int id)
{
var entityType = (EntityType)TempData["EntityType"];
var exists = await _responseResourceStringUiService.ResponseResourceStringExistsAsync(
id,
entityType);
return RedirectToRoute(!exists ?
RouteNames.ResponseResourceString_Home_Add :
RouteNames.ResponseResourceString_Home_Edit,
new {id, entityType});
}....
}
public class PublicationController : Controller
{
public async Task<IActionResult> Index()
{
var vm = new PublicationViewModel
{
...
};
TempData["EntityType"] = InboxEntityType.Publication;
........
}
My question is - is there more elegant way to achieve this without the enum value beeing in the url after the redirection.
I was thinking for example to create an abstract property of thids Enum Type in this ResponseResourceController
AND the other controller PublicationController(and othe that are going to do that) to inherit it and override the property with the right enum value and as the ResponseResourceController will have property I will not need the entity type as parameter in the Add and Edit Action.

Answer 1

Why don't just directly call the PublicationController and avoid creating an unnecessary redirect? You can distinguish directly in the frontend if it is a new or an existing record.
If you wanna use this method for creating new records then you should prefer to use a POST request instead of GET.

Answer 2

In short, multiple controllers does not work and url redirection is not necessary.
From the description I think what you really want is displaying the add/edit form base on an ID (with your temp entity type stored in somewhere). If this is what you want then single controller with multiple views should be able to handle that.
What will happen when you create multiple controllers?
The routing rules in the app has to be unique. If you have a ResponseResourceController and a PublicationController and each of them has the Index action, what will be the routes look like?
You probably need to define a route like /ResponseResource/Index for ResponseResourceController.Index() and a route like /Publication/Index for PublicationController.Index(). If there is a EntityType called Bob, you may need to define a route like /Bob/Index and create a BobController.
However, if you try to name a unique route for each of the EntityType, your route has to contain that piece of information (either in the route or in the query string). So, creating a dedicated controller for each EntityType cannot solve your problem.
Multiple views for multiple entity types
If you don't want to include the EntityType in the url, you may use ResponseResourceController.Index(int id) to get the entity ID and respond with different views for different EntityType:
[Route("/response-resource")]
public class ResponseResourceController : Controller
{
[HttpGet("")]
public async Task<IActionResult> Index(int id)
{
var entityType = (EntityType)TempData["EntityType"];
var exists = await _responseResourceStringUiService.ResponseResourceStringExistsAsync(id, entityType);
var viewName = exists ? "_AddEntity" : "_EditEntity";
var vm = new GenericViewModel
{
type = entityType,
/* other fields */
}
return View(viewName, vm); // so user may see a different view under different situation
}
}
And for the view model:
public class GenericViewModel
{
public EntityType type { get; set; }
}
You also need to define 2 views: _AddEntity and _EditEntity. In the above example, GenericViewModel contains the EntityType so you will know which entity you are handling.
Furthermore, you can even define a dedicated view for each EntityType and pass a dedicated view model to that view. e.g. PublicationViewModel will be the view model used in _AddPublication and _EditPublication views.
Expected behavior
When user requests for ResponseResource with and id, e.g. /response-resource?id=123, your application will render the view base on the id and the EntityType. No url redirection and url won't change.