Delphi DLL

Socket Send and Receive BinData

Demonstrates the Chilkat Socket ReceiveBdN and SendBd methods. Delphi DLL

uses
    Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
    Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, BinData, Socket;

...

procedure TForm1.Button1Click(Sender: TObject);
var
success: Boolean;
sock: HCkSocket;
useTls: Boolean;
port: Integer;
maxWaitMs: Integer;
bdToSend: HCkBinData;
i: Integer;
byteVal: Integer;
bdRecv: HCkBinData;

begin
success := False;

// This example requires the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

sock := CkSocket_Create();

// --------------------------------------------------------------------
// This example uses the public TCP echo service at https://tcpbin.com/
// --------------------------------------------------------------------

useTls := False;
port := 4242;
maxWaitMs := 5000;
success := CkSocket_Connect(sock,'tcpbin.com',port,useTls,maxWaitMs);
if (success = False) then
  begin
    Memo1.Lines.Add(CkSocket__lastErrorText(sock));
    Exit;
  end;

// Wait a max of 2 seconds for a response..
CkSocket_putMaxReadIdleMs(sock,2000);

// Send 26 bytes contained in a Chilkat BinData
bdToSend := CkBinData_Create();
i := 0;
byteVal := 65;
while i < 26 do
  begin
    CkBinData_AppendByte(bdToSend,byteVal);
    byteVal := byteVal + 1;
    i := i + 1;
  end;

// Send the contents of the BinData
// Pass zero's in the 2nd and 3rd arguments to send the entire contents of the BinData.
CkSocket_SendBd(sock,bdToSend,0,0);

// The tcpbin.com echo server only echoes after receiving an LF (linefeed char)
CkSocket_SendByte(sock,10);

// The echo server will echo back whatever is sent to it.
// We should be able to read the same bytes back..
bdRecv := CkBinData_Create();
// Receive the 26 bytes previously sent, plus the LF char.
success := CkSocket_ReceiveBdN(sock,27,bdRecv);
if (success = False) then
  begin
    Memo1.Lines.Add(CkSocket__lastErrorText(sock));
    Exit;
  end;

// Show the contents of bdRecv in hex format
Memo1.Lines.Add(CkBinData__getEncoded(bdRecv,'hex'));

// Output:  4142434445464748494A4B4C4D4E4F505152535455565758595A0A

CkSocket_Dispose(sock);
CkBinData_Dispose(bdToSend);
CkBinData_Dispose(bdRecv);

end;