StringWriter sw = new StringWriter();
            XmlTextWriter tw = new XmlTextWriter(sw);

            XmlSerializerNamespaces xsn = new XmlSerializerNamespaces();

            XmlSerializer ser = new XmlSerializer(typeof(GerarNfseEnvio));
            FileStream arquivo = new FileStream("E:\NFSe-" + "RPS" + numero.ToString().PadLeft(15, '0') + ".xml", FileMode.CreateNew);
            xsn.Add("", "http://www.abrasf.org.br/nfse.xsd");

            ser.Serialize(arquivo, gerar, xsn);
            arquivo.Close();