keep me logged in

now wat if i want to remember my password.
lets say,i login a site with "keep me logged in" checked (ie a cookie is created) with a months expiry time,And i close the browser without logout.Now in this case i need to delete the cookies on browser close rt ??
public static void Login(HttpResponse response, string username, bool rememberMeChecked) { DateTime expiration = DateTime.Now.AddMonths(1); if (rememberMeChecked) { expiration = DateTime.Now.AddMonths(1); } FormsAuthentication.Initialize(); FormsAuthenticationTicket tkt = new FormsAuthenticationTicket(1, username, DateTime.Now, expiration, rememberMeChecked, FormsAuthentication.FormsCookiePath); HttpCookie ck = new HttpCookie(FormsAuthentication.FormsCookieName, FormsAuthentication.Encrypt(tkt)); ck.Path = FormsAuthenticat ...