string xmlPath = @"c:\temp2\ApDataImport.xml";
string sResult;
// Send XmlNode
XmlDocument doc = new XmlDocument();
XmlTextReader reader = new XmlTextReader(xmlPath);
reader.MoveToContent(); //Move to the cd element node.
//Create a node representing the cd element node.
XmlNode cd = doc.ReadNode(reader);
Service1 proxy = new Service1();
sResult = proxy.ApDataXmlNodeMethod(cd);