eBay GeteBayTime

        public static async Task<DateTime?> GeteBayTime()
        {
            // instantiate our client and response message
            HttpClient client = new HttpClient();
            HttpResponseMessage response = new HttpResponseMessage();

            // add headers
            client.DefaultRequestHeaders.Add("X-EBAY-API-APP-ID", "JacobGai-MyPerson-PRD-d721a6b08-37788a17");
            client.DefaultRequestHeaders.Add("X-EBAY-API-SITE-ID", "0");
            client.DefaultRequestHeaders.Add("X-EBAY-API-CALL-NAME", "GeteBayTime");
            client.DefaultRequestHeaders.Add("X-EBAY-API-VERSION", "863");
            client.DefaultRequestHeaders.Add("X-EBAY-API-REQUEST-ENCODING", "xml");

            string xml = File.ReadAllText("C:\\Temp\\eBayTimeRequest.xml");

            // post request as xml object
            var httpContent = new StringContent(xml);
            response = await client.PostAsync("https://api.ebay.com/shopping", httpContent);

            // return status
            if (response.IsSuccessStatusCode)
            {
                XmlDocument document = new XmlDocument();
                document.LoadXml(XDocument.Parse(response.Content.ReadAsStringAsync().Result).Root.ToString());
                string json = JsonConvert.SerializeXmlNode(document, Newtonsoft.Json.Formatting.Indented);

                dynamic obj = JsonConvert.DeserializeObject(json);
                DateTime ebaytime = DateTime.Parse(obj.GeteBayTimeResponse.Timestamp);

                return ebaytime;
            }
            return null;
        }