覆盖不适用于ASP.net Core MVC中的虚拟方法

Question

namespace ProjectA.Controllers
public partial class CustomerController : Controller
{
 public virtual IActionResult Index()
 {
  ...Some code here
 }

 public virtual IActionResult Login()
 {
  ...Some code here
 }
}


namespace ProjectB.Controllers
public partial class CustomerController : ProjectA.Controllers.CustomerController
{
 public override IActionResult Login()
 {
  ...Some code here
 }
}

When I try to override as above it gives me below error

AmbiguousActionException: Multiple actions matched. The following actions matched route data and had all constraints satisfied: ProjectA.Controllers.CustomerController.Index (ProjectA) ProjectB.Controllers.CustomerController.Index (ProjectB)

Though there is no Index action in ProjectB. When I change the name of the conroller of ProjectB as:

namespace ProjectB.Controllers
public partial class CustomCustomerController : ProjectA.Controllers.CustomerController
{
 public override IActionResult Login()
 {
  ...Some code here
 }
}

AmbiguousActionException is gone but still the override doesnt work. I dont get call in overriden action. Is it like .Net core doesnt support overriding any more because it works like charm without .net core with the same name of controllers. Please help..

Answer 1

As you have both class name as “CustomerController”. And both may have using default routing. So for both controllers url should be same as /{controller}/{action} .

So for same url there will be 2 actions available for each controllers. That is why you are getting

“AmbiguousActionException” exception.

When you change your child controller to “CustomCustomerController” then url will be changed for both controllers so no such ambiguity happen so it worked.

As you said override not working. In this case you have to use url as “/CustomCustomer/login” then it will go to Login action of CustomCustomerController.

EDIT 1

You can update your code as below and it should work fine. Create your controllers as below:

namespace ProjectA.Controllers {
    public partial class CustomerController : Controller
    {
        public virtual IActionResult Index()
        {
            ...Some code here
        }

        public virtual IActionResult Login()
        {
            ...Some code here
        }
    }
}

namespace ProjectB.Controllers {
    public partial class CustomCustomerController : ProjectA.Controllers.CustomerController
    {
        public override IActionResult Login()
        {
            ...Some code here
        }
    }
}

And Update app.UseMvc(routes => part into startup.cs as below. Add customer route before default route.

app.UseMvc(routes =>
{
    routes.MapRoute(
        name: "customer",
        template: "customer/{action}/{id?}",
        defaults: new { controller = "CustomCustomer", action = "Index" });

    routes.MapRoute(
        name: "default",
        template: "{controller=Home}/{action=Index}/{id?}");
});