Delphi client and ASMX service. Data not received by Operation

I have a built a simple ASMX service using Visual Studio 2010. I am have build a simple service client application (form) using Delphi 7. I have used WSDLImport to create a proxy file that contains all type definitions and service operations. Here is the code for the WebService11.pas file.

 unit WebService1;

interface

uses InvokeRegistry, SOAPHTTPClient, Types, XSBuiltIns;

type

  WebService1Soap = interface(IInvokable)
  ['{3392229C-09D2-6D56-CE62-6850ABB2629D}']
    function  Add(const a: Integer): Integer; stdcall;
    function  Subtract(const a: Integer; const b: Integer): Integer; stdcall;
  end;

function GetWebService1Soap(UseWSDL: Boolean=System.False; Addr: string=''; HTTPRIO: THTTPRIO = nil): WebService1Soap;


implementation

function GetWebService1Soap(UseWSDL: Boolean; Addr: string; HTTPRIO: THTTPRIO): WebService1Soap;
const
  defWSDL = 'http://localhost/DelphiTest/WebService1.asmx?wsdl';
  defURL  = 'http://localhost/DelphiTest/WebService1.asmx';
  defSvc  = 'WebService1';
  defPrt  = 'WebService1Soap';
var
  RIO: THTTPRIO;
begin
  Result := nil;
  i开发者_如何学Pythonf (Addr = '') then
  begin
    if UseWSDL then
      Addr := defWSDL
    else
      Addr := defURL;
  end;
  if HTTPRIO = nil then
    RIO := THTTPRIO.Create(nil)
  else
    RIO := HTTPRIO;
  try
    Result := (RIO as WebService1Soap);
    if UseWSDL then
    begin
      RIO.WSDLLocation := Addr;
      RIO.Service := defSvc;
      RIO.Port := defPrt;
    end else
      RIO.URL := Addr;
  finally
    if (Result = nil) and (HTTPRIO = nil) then
      RIO.Free;
  end;
end;


initialization
  InvRegistry.RegisterInterface(TypeInfo(WebService1Soap), 'http://tempuri.org/', 'utf-8');
  InvRegistry.RegisterDefaultSOAPAction(TypeInfo(WebService1Soap), 'http://tempuri.org/%operationName%');

end

.

Following is the file that is contained in the Unit1.pas file that is the actual code of the Form.

unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls, WebService1, InvokeRegistry, Rio, SOAPHTTPClient;

type
  TForm1 = class(TForm)
    Button1: TButton;
    HTTPRIO1: THTTPRIO;
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.Button1Click(Sender: TObject);
var c : integer;
begin
    c := GetWebService1Soap(False,'',HTTPRIO1).Add(10);
    ShowMessage(IntToStr(c));
    end;
end.

The delphi client is hitting the ASMX service as expected. However, I do not see the data sent as parameter in the "Add" operation. I put a break in the ASMX service source code and inspected the parameter value, which is null.

I have used fiddler to read the message sent by the delphi client, but I cannot see the incoming SOAP message. I can see the SOAP data sent back by the ASMX service, which is an integer value. This integer value is not received by the SOAP client.

I need to understand the following:

1) Is there any other way to read what is sent and received by delphi client. I know that there is a component HTTPRIO1 in Delphi, but I do not know how to I get the request and response data from it.

2) What am I doing wrong here.

*Please not that I am not an expert in Delphi 7 yet. I am basically trying to get a delphi client talk to an ASMX service. I could have used WCF but there is some complexity I am facing, therefore needs to understand if I can get the delphi client talk to a ASMX service based on SOAP 1.1

Added Later: I have somehow gathered the Request and Response SOAP messages through fiddler 2.

Request SOAP message:

<?xml version="1.0"?>
<SOAP-ENV:Envelope xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:SOAP-ENC="http://schemas.xmlsoap.org/soap/encoding/">
  <SOAP-ENV:Body SOAP-ENV:encodingStyle="http://schemas.xmlsoap.org/soap/encoding/">
    <NS1:Add xmlns:NS1="http://tempuri.org/">
           <a xsi:type="xsd:int">10</a>
    </NS1:Add></SOAP-ENV:Body>
</SOAP-ENV:Envelope>

Response SOAP message:

<?xml version="1.0" encoding="utf-8"?>
<soap:Envelope xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
<soap:Body>
<AddResponse xmlns="http://tempuri.org/">
<AddResult>2</AddResult>
</AddResponse>
</soap:Body>
</soap:Envelope>

---

I have fixed the issue. This was basically due to the SOAP format which wasn't compatible with WCF. I converted the SOAP format to 'Document/Literal'. Please read my other thread How to set THTTPRio.Converter.Options to soLiteralParams in OnBeforeExecuteEvent