Redirect From Action Filter Attribute

Question

What is the best way to do a redirect in an ActionFilterAttribute. I have an ActionFilterAttribute called IsAuthenticatedAttributeFilter and that checked the value of a session variable. If the variable is false, I want the application to redirect to the login page. I would prefer to redirect using the route name SystemLogin however any redirect method at this point would be fine.

Answer 1

Set filterContext.Result

With the route name:

filterContext.Result = new RedirectToRouteResult("SystemLogin", routeValues);

You can also do something like:

filterContext.Result = new ViewResult
{
    ViewName = SharedViews.SessionLost,
    ViewData = filterContext.Controller.ViewData
};

---

If you want to use RedirectToAction:

You could make a public RedirectToAction method on your controller (preferably on its base controller) that simply calls the protected RedirectToAction from System.Web.Mvc.Controller. Adding this method allows for a public call to your RedirectToAction from the filter.

public new RedirectToRouteResult RedirectToAction(string action, string controller)
{
    return base.RedirectToAction(action, controller);
}

Then your filter would look something like:

public override void OnActionExecuting(ActionExecutingContext filterContext)
{
    var controller = (SomeControllerBase) filterContext.Controller;
    filterContext.Result = controller.RedirectToAction("index", "home");
}