ASP.Net Core MVC RedirectToAction is appending controller name in front of returnUrl

Question

I am working on a ASP.Net core, MVC 6 application. I have an AppControler as my initial controller and if a user tries to go to an action that has an [Authorize] attribute, I redirect to my AuthController for the login, passing in the returnUrl for the return. Once authenticated, I use ... return RedirectToAction(returnUrl).

In debug, I can see that the returnUrl string is set to /App/Timesheets. However, in the browser address bar, it has an address of http://localhost:49940/Auth/%2FApp%2FTimeSheets . For some reason it is appending the controller name (Auth) in front of the returnUrl.

Here is my Login action in the AuthController

    [HttpPost]
    public async Task<ActionResult> Login(LoginViewModel vm, string returnUrl)
    {
        if (ModelState.IsValid)
        {
            var signInResult = await _signInManager.PasswordSignInAsync(vm.Username, vm.Password, true, false);

            if (signInResult.Succeeded)
            {
                if (string.IsNullOrWhiteSpace(returnUrl))
                {
                    return RedirectToAction("Timesheets", "App");
                }
                else
                {
                    return RedirectToAction(returnUrl);
                }
            }
            else
            {
                ModelState.AddModelError("", "Username or password incorrect");
            }
        }

        return View();
    }

I can manually enter http://localhost:49940/App/Timesheets in the browser address bar and get to the correct view. Also, if I add

returnUrl = String.Empty;  //Test Only

before the line...

if (string.IsNullOrWhiteSpace(returnUrl))

to cause it to execute the line...

return RedirectToAction("Timesheets", "App");

The redirection works just fine. So it has something to do with passing in a string variable in the "/Controller/Action" format that is the problem.

Any ideas?

Answer 1

When you have a full URL already, you should return a Redirect . Currently you are doing a RedirectToAction which will try to redirect to an action under the current controller (Auth).

if (signInResult.Succeeded)
{
   if (string.IsNullOrWhiteSpace(returnUrl))
   {
      return RedirectToAction("Timesheets", "App");
   }
   else
   {
      return Redirect(returnUrl);
   }
}

Answer 2

var redirect = RedirectToAction();
redirect.ActionName = "YourAction"; // or can use nameof("") like  nameof(YourAction);
redirect.ControllerName= "YourCtrl"; // or can use nameof("") like  nameof(YourCtrl);
return redirect;

Answer 3

I guess it just took writing out the problem description for me to see the problem.

I changed...

return RedirectToAction(returnUrl);

to...

return RedirectToAction(WebUtility.UrlEncode(returnUrl));

and now it is working properly.

:/