File Upload via HTTP POST

var client = new RestClient("http://sa.yourlawyer.com:8081/SATestFileUpload/Fileupload.asmx");
var request = new RestRequest(Method.POST);
request.AddHeader("postman-token", "49867e69-f578-9149-96e5-173d60d7b8b3");
request.AddHeader("cache-control", "no-cache");
request.AddHeader("content-type", "text/xml");
request.AddParameter("text/xml", "<?xml version=\"1.0\" encoding=\"utf-8\"?>\r\n<soap12:Envelope xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" xmlns:xsd=\"http://www.w3.org/2001/XMLSchema\" xmlns:soap12=\"http://www.w3.org/2003/05/soap-envelope\">\r\n  <soap12:Body>\r\n    <UploadFile xmlns=\"http://localhost/\">\r\n      <f>base64Binary</f>\r\n      <fileName>test.xml</fileName>\r\n      <caseNumber>1802864</caseNumber>\r\n    </UploadFile>\r\n  </soap12:Body>\r\n</soap12:Envelope>", ParameterType.RequestBody);
IRestResponse response = client.Execute(request);