Реализация Hook-a

library Meneger_dll;
uses SysUtils, Classes, Windows, Messages;

const
KeyEvent=WM_USER+1;
WinTitle='Key_Meneger';

var HookHandle: HHOOK;

function KeyHook(code: integer; WParam: word; lParam: Longint):Longint;stdcall;
var Wnd: hWnd;
begin
if (code=HC_ACTION) and (lParam <> lParam or $8000 shl 16) and (lParam <> lParam or $8000 shl 15) then
begin
    Wnd:=FindWindow(WinTitle, nil);
    SendMessage(Wnd, KeyEvent, wParam, lParam);
end;
Result:=CallNextHookEx(HookHandle, code, WParam, lParam);
end;

procedure SetKeyHook; export;
begin
HookHandle:=SetWindowsHookEx(WH_KEYBOARD, @KeyHook, hInstance, 0);
end;

procedure DelKeyHook; export;
begin
if HookHandle <> 0 then UnhookWindowsHookEx(HookHandle);
HookHandle:=0;
end;

exports
SetKeyHook name 'SetKeyHook',
DelKeyHook name 'DelKeyHook';

begin
end.

unit Unit1;
interface
uses Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms, Dialogs, StdCtrls;

const
KeyEvent=WM_USER+1;
DllName='Meneger_dll';

type
  TForm1 = class(TForm)
    Label1: TLabel;
    procedure FormCreate(Sender: TObject);
    procedure FormClose(Sender: TObject; var Action: TCloseAction);
    procedure FormDestroy(Sender: TObject);
  private
    { Private declarations }
  procedure WM_new(var M: TMessage);
  message KeyEvent;
  public
    { Public declarations }
  end;

var Form1: TForm1;
     P:Pointer;
     hLib:THandle;

implementation

{$R *.dfm}

function SetKeyHook: Longint; external DllName name 'SetKeyHook';
function DelKeyHook: Longint; external DllName name 'DelKeyHook';

procedure Tform1.WM_new(var M: TMessage);  //это я сам не знаю что написал - выдрал с какого-то примера
begin
Label1.Caption:='NEW';
end;

procedure TForm1.FormCreate(Sender: TObject);
begin
hLib:=LoadLibrary(DllName);
SetKeyHook;
end;

procedure TForm1.FormClose(Sender: TObject; var Action: TCloseAction);
begin
FreeLibrary(hLib);
DelKeyHook;
end;

procedure TForm1.FormDestroy(Sender: TObject);
begin
FreeLibrary(hLib);
DelKeyHook;
end;

end.