CSHARP

if session is not active then redirect to login page mvc.net

public class AuthorizeActionFilterAttribute : ActionFilterAttribute
    {
      public override void OnActionExecuting(FilterExecutingContext filterContext)
      {
        HttpSessionStateBase session = filterContext.HttpContext.Session;
        Controller controller = filterContext.Controller as Controller;

        if (controller != null)
        {
          if (session != null && session ["authstatus"] == null)
          {
filterContext.Result =
       new RedirectToRouteResult(
           new RouteValueDictionary{{ "controller", "Login" },
                                          { "action", "Index" }

                                         });
          }
        }

        base.OnActionExecuting(filterContext);
      }
    }
more details in here:

https://stackoverflow.com/a/5453371/1384539