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How to use records with TIdTCPClient in Delphi

Posted on 2009-06-29
2
1,396 Views
Last Modified: 2013-11-13
Hi,

I'm using Delphi 7 and Indy 9 to send data to a Server. In my code, I use a record that I initialize first and then pass it to the WriteBuffer of WriteStream. Most of the record fields are sent normally except for the string field that seems to send garbage instead of the characters I initialized it with.

Anyone can help me with that? or Is there an example somewhere so that I can base my ork on?

Thanks
unit frmClient;
 

interface
 

uses

  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,

  Dialogs, StdCtrls, IdBaseComponent, IdComponent, IdTCPConnection,

  IdTCPClient, ExtCtrls, IdAntiFreezeBase, IdAntiFreeze;
 

type

  TProcolFrameSend = packed record

    iLength: Integer;

    iType: Integer;

    iID: Integer;

    iControl: Integer;

    iNbrSeries: Integer;

    iNbrParams: Integer;

    iParamLength: Integer;

    sParamValue: string;

  end;
 

  TForm1 = class(TForm)

  // objets and procedures deleted to simplify code...

  private

    { Private declarations }

  public

    { Public declarations }

  end;
 

var

  Form1: TForm1;
 

implementation
 

{$R *.dfm}
 

procedure TForm1.cmdConnectClick(Sender: TObject);

  var

    imgStream : TMemoryStream;

    longTrame : integer;

begin

  If tcpClientSkt.Connected Then

  begin

    mStatus.Lines.Add('Already connected to server.');

    Exit;

  end;

  mStatus.Clear;

  mStatus.Lines.Add('Connecting to server');

  try

    tcpClientSkt.Host := 'CMV-10001-11019';

    tcpClientSkt.Port := 5001;

    tcpClientSkt.Connect(5000);

    mStatus.Lines.Add(tcpClientSkt.ReadLn());

  except

    on E: Exception do MessageDlg ('Error connecting to server'+#13+E.Message, mtError, [mbOk], 0);

  end;

end;
 

procedure TForm1.tcpClientSktConnected(Sender: TObject);

begin

  mStatus.Lines.Add('Conneted to server ' + tcpClientSkt.Host);

end;
 

procedure TForm1.FormClose(Sender: TObject; var Action: TCloseAction);

begin

  If tcpClientSkt.Connected Then

  begin

    mStatus.Lines.Add('Deconnecting from server');

    tcpClientSkt.Disconnect();

  end

end;
 

procedure TForm1.cmdDisconnectClick(Sender: TObject);

begin

  If tcpClientSkt.Connected Then

  begin

    mStatus.Clear;

    mStatus.Lines.Add('Deconnecting from server');

    tcpClientSkt.Disconnect();

  end

end;
 

procedure TForm1.tcpClientSktDisconnected(Sender: TObject);

begin

  mStatus.Lines.Add('Disconnected from server');

end;
 

procedure TForm1.FormCreate(Sender: TObject);

begin

  mStatus.Clear;

end;
 

procedure TForm1.Button2Click(Sender: TObject);

var

  FrameSend: TProcolFrameSend;

  inBuf : TMemoryStream;

  i : Integer;

  tempStr : AnsiString;

begin
 

  // Control Info

  FrameSend.iType := 30104;

  FrameSend.iID := 0;

  FrameSend.iControl := 0;

  FrameSend.iNbrSeries := 1;

  FrameSend.iNbrParams := 2;
 

  // param length

  FrameSend.iParamLength := StrLen(PChar(ListBox1.Items[ListBox1.ItemIndex]));

  // Frame total lenght

  FrameSend.iLength := 28 + FrameSend.iParamLength;
 

  // Parameter value, the name of a file to be sent by the server

  FrameSend.sParamValue := ListBox1.Items[ListBox1.ItemIndex];
 

  If tcpClientSkt.Connected Then

  begin

    try
 

      tcpClientSkt.OpenWriteBuffer(-1);

      tcpClientSkt.SendBufferSize := FrameSend.iLength;

      tcpClientSkt.WriteBuffer(FrameSend, FrameSend.iLength, true);

      tcpClientSkt.CloseWriteBuffer();
 

      inBuf := TMemoryStream.Create;

      tcpClientSkt.ReadStream(inBuf);

      inBuf.Position := 0;
 

      mStatus.Lines.Add('Document received');
 

    finally

      if tcpClientSkt.Connected then inBuf.Free;

    end;

  end;

end;
 

end.

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0
Comment
Question by:pmaltais
2 Comments
 
LVL 18

Accepted Solution

by:
Johnjces earned 500 total points
ID: 24736912
If you download the Indy demos, there is a sample application called SendReceiveRecords as I recall, that sends binary images.

Might be exactly what you need to base your work form.

http://www.indyproject.org/demos/index.html

John
0
 

Author Closing Comment

by:pmaltais
ID: 31597934
Thanks. The demos really helped.
0

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