Check Ports

uses Winsock

//

function PortTCPIsOpen(dwPort : Word; ipAddressStr:string) : boolean;
var
      client : sockaddr_in;
      sock   : Integer;
begin
        client.sin_family      := AF_INET;
        client.sin_port        := htons(dwPort);
        client.sin_addr.s_addr := inet_addr(PChar(ipAddressStr));
        sock  :=socket(AF_INET, SOCK_STREAM, 0);
        Result:=connect(sock,client,SizeOf(client))=0;
end;

procedure Ports();
var
  ret    : Integer;
  wsdata : WSAData;
begin
  Form1.Memo1.Lines.Add('Init WinSock');
  ret := WSAStartup($0002, wsdata);
  if ret <> 0 then exit;
  try
    Form1.Memo1.Lines.Add('Description : '+wsData.szDescription);
    Form1.Memo1.Lines.Add('Status      : '+wsData.szSystemStatus);

    if PortTCPIsOpen(80 , '192.168.0.1') then // Hier können Port und IP bestimmt werden.
    Form1.Memo1.Lines.Add('Open')
    else
    Form1.Memo1.Lines.Add('Close');

  finally
  WSACleanup; //terminates use of the Winsock
  end;
end;

Beispiel :

procedure TForm1.Button1Click(Sender: TObject);
begin
  ports();
end;