(Delphi DLL) Accept Connection on Socket

Demonstrates how to create a TCP/IP socket, listen on a port, accept an incoming connection, and send a "Hello World" message to the client.

Chilkat for Delphi Downloads Chilkat non-ActiveX DLL for Delphi Chilkat ActiveX DLL for Delphi * The examples here use the non-ActiveX DLL.

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

...

procedure TForm1.Button1Click(Sender: TObject);
var
listenSocket: HCkSocket;
success: Boolean;
connectedSocket: HCkSocket;

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

listenSocket := CkSocket_Create();

// Bind to a port and listen for incoming connections:
// This example will listen at port 5555 and allows for a backlog
// of 25 pending connection requests.
success := CkSocket_BindAndListen(listenSocket,5555,25);
if (success <> True) then
  begin
    Memo1.Lines.Add(CkSocket__lastErrorText(listenSocket));
    Exit;
  end;

// Get the next incoming connection
// Wait a maximum of 20 seconds (20000 millisec)

connectedSocket := CkSocket_AcceptNextConnection(listenSocket,20000);
if (CkSocket_getLastMethodSuccess(listenSocket) = False) then
  begin
    Memo1.Lines.Add(CkSocket__lastErrorText(listenSocket));
    Exit;
  end;

// Set maximum timeouts for reading an writing (in millisec)
CkSocket_putMaxReadIdleMs(connectedSocket,10000);
CkSocket_putMaxSendIdleMs(connectedSocket,10000);

// Send a "Hello World!" message to the client:
success := CkSocket_SendString(connectedSocket,'Hello World!');
if (success <> True) then
  begin
    Memo1.Lines.Add(CkSocket__lastErrorText(connectedSocket));
    CkSocket_Dispose(connectedSocket);
    Exit;
  end;

// Close the connection with the client.
// Wait a max of 20 seconds (20000 millsec)
success := CkSocket_Close(connectedSocket,20000);

Memo1.Lines.Add('success!');

CkSocket_Dispose(listenSocket);

end;