//ham lay gi tri cua mot cookie tu may client
 static public void getCookie(ref string MemberID, ref string Role)
 {
     if (HttpContext.Current.Request.Cookies["PSC_UIS"] != null)
     {
         MemberID = Encrypt_Decrypt.Instance().Decrypt(HttpContext.Current.Request.Cookies["PSC_UIS"]["1"].ToString());
         Role     = Encrypt_Decrypt.Instance().Decrypt(HttpContext.Current.Request.Cookies["PSC_UIS"]["2"].ToString());
     }
 }
    static public void writeCookie(string MemberID, string Role)
    {
        //encrypt.
        string encryptMemberID = Encrypt_Decrypt.Instance().Encrypt(MemberID);
        string encryptRole     = Encrypt_Decrypt.Instance().Encrypt(Role);

        //set cookies.
        HttpContext.Current.Response.Cookies["PSC_UIS"]["1"]    = encryptMemberID;
        HttpContext.Current.Response.Cookies["PSC_UIS"]["2"]    = encryptRole;
        HttpContext.Current.Response.Cookies["PSC_UIS"].Expires = DateTime.Now.AddYears(1);
    }