public static void SetCookie(string userName, bool persistent, UserData data)
{
var encodedUserData = CookieHelper.EncodeUserData(data);
var ticket = new FormsAuthenticationTicket(
1,
userName,
DateTime.Now,
DateTime.Now.Add(FormsAuthentication.Timeout),
persistent,
encodedUserData,
FormsAuthentication.FormsCookiePath
);
var encryptedTicket = FormsAuthentication.Encrypt(ticket);
var cookie = new HttpCookie(FormsAuthentication.FormsCookieName, encryptedTicket);
HttpContext.Current.Response.SetCookie(cookie);
}