//----------------------------------------------------------------
function getIPs(Str:String): Tstrings;
type
  TaPInAddr = array[0..10] of PInAddr;
  PaPInAddr = ^TaPInAddr;
var
  phe: PHostEnt;
  pptr: PaPInAddr;
  I: Integer;
  GInitData: TWSAData;
begin
  WSAStartup($101, GInitData);
  Result := TstringList.Create;
  Result.Clear;
  phe := GetHostByName(PAnsiChar(Str));
  if phe = nil then Exit;
  pPtr := PaPInAddr(phe^.h_addr_list);
  I    := 0;
  while pPtr^[I] <> nil do
  begin
    Result.Add(inet_ntoa(pptr^[I]^));
    Inc(I);
  end;
  WSACleanup;
end;
//----------------------------------------------------------------
procedure TForm1.Button1Click(Sender: TObject);
begin

  if Edit1.Text <> '' then
  begin
     Memo1.Clear;
     Memo1.Lines := GetIPs(Edit1.Text);
      if Memo1.Lines.Count = 0 then ShowMessage('Invalided HostName');
  end
    else ShowMessage('Please enter a HostName');

end;