private void button1_Click(object sender, EventArgs e) { Prescription ordo = new Prescription(); Patient pat = new Patient(); PrescriptionLine line = new PrescriptionLine(); line.drugId = 4002; line.drugType = "PRODUCT"; List<PrescriptionLine> lines = new List<PrescriptionLine>(); lines.Add(line); ordo.patient = pat; ordo.prescriptionlines = lines; XmlSerializer xs = new XmlSerializer(typeof(Prescription)); StringWriter serial = new Utf8StringWriter(); xs.Serialize(serial, ordo); string data = serial.ToString(); byte[] dataByte = Encoding.UTF8.GetBytes(data); HttpWebRequest httpWReq = (HttpWebRequest)WebRequest.Create("http://apirest-beta.vidal.fr/rest/api/alerts"); httpWReq.Method = "POST"; httpWReq.ContentType = "text/xml"; httpWReq.ContentLength = dataByte.Length; using (Stream newStream = httpWReq.GetRequestStream()) { newStream.Write(dataByte, 0, dataByte.Length); newStream.Close(); } WebResponse response = httpWReq.GetResponse(); StreamReader reader = new StreamReader(response.GetResponseStream()); string ResponseMessage = reader.ReadToEnd(); response.Close(); }