{
 Microsoft® Internet Explorer Version 4.0 introduces the IP address control,
 a new control similar to an edit control that allows the user to enter a
 numeric address in Internet protocol (IP) format.
 This format consists of four three-digit fields.
 Each field is treated individually; the field numbers are zero-based and
 proceed from left to right as shown in this figure.
 Further informations
 http://msdn.microsoft.com/library/en-us/shellcc/platform/commctls/ipaddress/ipaddress.asp
}
unit Unit1;
interface
uses
 Windows, Messages, Classes, Forms, Controls, StdCtrls, ExtCtrls;
type
 TForm1 = class(TForm)
  IPAddress: TBevel;
  SetIP: TButton;
  ClearIP: TButton;
  procedure FormCreate(Sender: TObject);
  procedure SetIPClick(Sender: TObject);
  procedure ClearIPClick(Sender: TObject);
 private
  FIPAddress: Longint;
  HIPAddress: HWND;
  PrevWndProc: TWndMethod;
  procedure NewWindowProc(var Message: TMessage);
 public
 end;
var
 Form1: TForm1;
implementation
{$R *.dfm}
uses
 CommCtrl;
const
 IP_ADDRESS_ID: Longword = $0100;
procedure TForm1.FormCreate(Sender: TObject);
var
 lpInitCtrls: TInitCommonControlsEx;
begin
 lpInitCtrls.dwSize := SizeOf(TInitCommonControlsEx);
 lpInitCtrls.dwICC := ICC_INTERNET_CLASSES;
 if InitCommonControlsEx(lpInitCtrls) then
 begin
  PrevWndProc := WindowProc;
  WindowProc := NewWindowProc;
  HIPAddress := CreateWindowEx(WS_EX_LEFT, WC_IPADDRESS, nil,
  WS_CHILD + WS_VISIBLE + WS_BORDER + WS_TABSTOP,
  IPAddress.Left, IPAddress., IPAddress.Width, IPAddress.Height,
  Handle, IP_ADDRESS_ID, HInstance, nil);
  SendMessage(HIPAddress, IPM_SETFOCUS, 0, 0);
 end;
end;
procedure TForm1.NewWindowProc(var Message: TMessage);
var
 nField: longint;
begin
 case Message.Msg of
  WM_NOTIFY:
  begin
  if PNMHDR(Ptr(Message.lParam)).idFrom = IP_ADDRESS_ID then
  begin
  case PNMIPAddress(ptr(Message.lParam)).hdr.code of
  IPN_FIELDCHANGED:
  begin
  if SendMessage(HIPAddress, IPM_ISBLANK, 0, 0) = 0 then
  SendMessage(HIPAddress, IPM_GETADDRESS, 0, lParam(LPDWORD(@FIPAddress)));
  end;
  end;
  end;
  end;
  WM_COMMAND:
  begin
  if Message.WParamLo = IP_ADDRESS_ID then
  case Message.WParamHi of
  EN_SETFOCUS:
  begin
  nField := SendMessage(HIPAddress, IPM_GETADDRESS, 0,
  lParam(LPDWORD(@FIPAddress)));
  if nField = 4 then nField := 0;
  SendMessage(HIPAddress, IPM_SETFOCUS, wParam(nField), 0);
  end;
  EN_KILLFOCUS:
  begin
  if SendMessage(HIPAddress, IPM_ISBLANK, 0, 0) = 0 then
  SendMessage(HIPAddress, IPM_GETADDRESS, 0, lParam(LPDWORD(@FIPAddress)));
  end;
  EN_CHANGE:
  begin
  end;
  end;
  end;
 end;
 if Assigned(PrevWndProc) then PrevWndproc(Message);
end;
procedure TForm1.SetIPClick(Sender: TObject);
begin
 FIPAddress := MAKEIPADDRESS(127, 0, 0, 1);
 SendMessage(HIPAddress, IPM_SETADDRESS, 0, lParam(DWORD(FIPAddress)));
end;
procedure TForm1.ClearIPClick(Sender: TObject);
begin
 SendMessage(HIPAddress, IPM_CLEARADDRESS, 0, 0);
end;
end.