Which is the simplest way to redirect to page when user is not logged in in ASP.NET MVC?-CodePudding

I have two simple login and home controllers:

public class LoginController : Controller
{
        public LoginController()
        {
            
        }

        public IActionResult Index()
        {
            return View();
        }
}

public class HomeController : Controller
    {
        public HomeController()
        {
            
        }

        public IActionResult Index()
        {
            return View();
        }

    }

I would like to redirect to login/index every time when user is not logged in. How can I achieve that? Thank you very much.

CodePudding user response：

You can use Authorize attribute which as part of Forms authentication in ASP.NET-MVC. To do that you need to setup forms authentication first in your web.config:

Under the <system.web> element, place:

<authentication mode="Forms">
  <forms loginUrl="~/Login/Index" timeout="45" slidingExpiration="true" cookieless="UseCookies" protection="All" requireSSL="false" enableCrossAppRedirects="false" defaultUrl="~/Home/Index" path="/" />
</authentication>

Now in your LoginController, when you are authenticating a user, it will be something like this:

public class LoginController : Controller
{
        public LoginController()
        {
            
        }

        public IActionResult Index()
        {               
            return View();
        }
        
        [HttpPost]
        [AllowAnonymous]
        public IActionResult ValidateUser()
        {
          //your user authentication logic here
          if(userAuthenticated)
          {
             FormsAuthentication.SetAuthCookie(userModel, false);
          }
  
           return View("Index");
        }
}

Once you have authenticated your user, then you can place the Authorize attribute either on class action or method depending on your need:

Require authorized user only to access entire class and its methods:

[Authorize]
public class HomeController : Controller
{
    public HomeController()
    {
        
    }

    public IActionResult Index()
    {
        return View();
    }

}

Require user to only be authorized for Index method:

public class HomeController : Controller
{
    public HomeController()
    {
        
    }

    [Authorize]
    public IActionResult Index()
    {
        return View();
    }

}