unit UFrmMain;interfaceuses  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,  Dialogs, StdCtrls;type  TForm1 = class(TForm)    btnClose: TButton;    btnSetHook: TButton;    btnSizeLongInt: TButton;    procedure btnCloseClick(Sender: TObject);    procedure btnSetHookClick(Sender: TObject);    procedure btnSizeLongIntClick(Sender: TObject);  private    { Private declarations }  public    { Public declarations }  end;var  Form1: TForm1;implementation{$R *.dfm}var    hHookKeyboard : HHOOK;procedure TForm1.btnCloseClick(Sender: TObject);begin    close;end;function MouseHook(code: Integer; wparam: WPARAM; lparam: LPARAM): LRESULT stdcall;begin    result := 1;end;function KeyHook(code: Integer; wparam: WPARAM; lparam: LPARAM): LRESULT stdcall;begin    if (wparam = vk_f4) and ((lparam and (1 shl 29)) > 0) then        result := 1    else        result := CallNextHookEx(hHookKeyboard, code, wparam, lparam);end;procedure TForm1.btnSetHookClick(Sender: TObject);begin    SetWindowsHookEx(WH_MOUSE,@MouseHook,HInstance,GetCurrentThreadId());    hHookKeyboard := SetWindowsHookEx(WH_KEYBOARD,@KeyHook,HInstance,GetCurrentThreadId());end;procedure TForm1.btnSizeLongIntClick(Sender: TObject);begin    ShowMessageFmt(‘sizeof longint:%d‘,[sizeof(longint)]);end;end.

//HookLibInterface.pasunit HookLibInterface;interfaceUSES    windows;{$IFNDEF HookLibInterface}    procedure SetHook(hwnd1:HWND); stdcall;    procedure UnHook(); stdcall;{$ENDIF}implementation{$IFNDEF HookLibInterface}    procedure SetHook(hwnd1:HWND); external ‘HookLib.dll‘ name ‘SetHook‘;    procedure UnHook(); external ‘HookLib.dll‘ name ‘UnHook‘;{$ENDIF}end.

//HookLib.dprlibrary HookLib;{ Important note about DLL memory management: ShareMem must be the  first unit in your library‘s USES clause AND your project‘s (select  Project-View Source) USES clause if your DLL exports any procedures or  functions that pass strings as parameters or function results. This  applies to all strings passed to and from your DLL--even those that  are nested in records and classes. ShareMem is the interface unit to  the BORLNDMM.DLL shared memory manager, which must be deployed along  with your DLL. To avoid using BORLNDMM.DLL, pass string information  using PChar or ShortString parameters. }uses  SysUtils,  Classes,  Windows,  Messages,  Dialogs,  HookLibInterface in ‘HookLibInterface.pas‘;{$R *.res}var    hMouseHook : HHOOK;    hKeyboardHook : HHOOK;var    g_hwnd : HWND;    function MouseHookProc(code: Integer; wparam: WPARAM; lparam: LPARAM): LRESULT stdcall;begin    result := 1;end;function KeyboardHookProc (code: Integer; wparam: WPARAM; lparam: LPARAM): LRESULT stdcall;begin    if vk_f2 = wparam then    begin        PostMessage(g_hwnd,wm_close,0,0);        //UnhookWindowsHookEx(hMouseHook);        UnhookWindowsHookEx(hKeyboardHook);    end;    result := 1;end;procedure SetHook(hwnd1 : HWND); stdcall;begin    g_hwnd := hwnd1;    //hMouseHook := SetWindowsHookEx(WH_MOUSE, MouseHookProc, GetModuleHandle(‘HookLib.dll‘),0);    hKeyboardHook := SetWindowsHookEx(WH_KEYBOARD, KeyboardHookProc, GetModuleHandle(‘HookLib.dll‘),0);    showmessage(‘成功加载勾子程序!‘);end;procedure UnHook(); stdcall;begin    //UnhookWindowsHookEx(hMouseHook);    UnhookWindowsHookEx(hKeyboardHook);    showmessage(‘成功取消勾子程序!‘);end;exports    SetHook,    Unhook;end.

unit UMain;interfaceuses  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,  Dialogs, StdCtrls;type  TFrmMain = class(TForm)    btnClose: TButton;    btnHookMouse: TButton;    btnUnHookMouse: TButton;    procedure btnCloseClick(Sender: TObject);    procedure btnHookMouseClick(Sender: TObject);    procedure btnUnHookMouseClick(Sender: TObject);    procedure FormCreate(Sender: TObject);  private    { Private declarations }  public    { Public declarations }  end;var  FrmMain: TFrmMain;implementationuses    HookLibInterface;{$R *.dfm}procedure TFrmMain.btnCloseClick(Sender: TObject);begin    close;end;procedure TFrmMain.btnHookMouseClick(Sender: TObject);begin                             SetHook(application.Handle);end;procedure TFrmMain.btnUnHookMouseClick(Sender: TObject);begin    UnHook;end;procedure TFrmMain.FormCreate(Sender: TObject);begin    SetWindowPos(self.Handle,HWND_TOPMOST,0,0,screen.Width,Screen.Height,SWP_SHOWWINDOW	);end;end.