I am getting an error back and following the API manual I received on how to encode my request. Below is my request..
string url = "[My url to send request to]";
string xmlrequest = "<serv_request><head><securityContext><account>[account]</account><key>[my account key]</key></securityContext></head><body><username>[my user name]</username></body></serv_request>";
NameValueCollection nvc = new NameValueCollection();
nvc.Add("xml", Server.UrlEncode(xmlrequest));
WebClient client = new WebClient();
byte[] byteresponse = client.UploadValues(url, nvc);
string xmlresponse = client.Encoding.GetString(byteresponse);
I am getting a response back with the error. Invalid at the top level of document.
Edit.. Adding the Instructions from the API Manual provided to me..
string url = " http://[domain_name]/_gateway/api/[filename].asp";
// formulate the XML request here
string xmlrequest = "<serv_request>...</serv_request>";
NameValueCollection nvc = new NameValueCollection();
nvc.Add("xml", Server.UrlEncode(xmlrequest));
WebClient client = new WebClient();
byte[] byteresponse = client.UploadValues(url, nvc);
string xmlresponse = client.Encoding.GetString(byteresponse);
It sounds like the server is not responding with a proper xml, it may be returning an empty string or any text that is not a well formed XML.
Try and capture the xml you are sending and use a tool like soapUI to send the request and see the response it gives to you.
Also maybe try this in stead of your last line of code:
string xmlresponse = System.Text.Encoding.UTF8.GetString(byteresponse);