Отключить клавиши при системном Hooke

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Отключить клавиши при системном Hooke[править | править код]

Winhook.dpr[править | править код]

{
  ** What is a Hook? **

  A hook is a point in the system message-handling mechanism where an
  application can install a subroutine to monitor the message traffic in
  the system and process certain types of messages before they reach the target window procedure.

  To use the Windows hook mechanism, a program calls the SetWindowsHookEx() API function,
  passing the address of a hook procedure that is notified when the specified
  event takes place. SetWindowsHookEx() returns the address of the previously installed
  hook procedure for the same event type. This address is important,
  because hook procedures of the same type form a kind of chain.
  Windows notifies the first procedure in the chain when an event occurs,
  and each procedure is responsible for passing along the notification.
  To do so, a hook procedure must call the CallNextHookEx() API function,
  passing the previous hook procedure's address.

  --> All system hooks must be located in a dynamic link library.

  ** The type of Hook used in this Example Code: **

  The WH_GETMESSAGE hook enables an application to monitor/intercept messages
  about to be returned by the GetMessage or PeekMessage function.
}

{
** Hook Dll - WINHOOK.dll **
WINHOOK.dpr
       |-----WHookInt.pas

** Interface unit ** WHookDef.dpr
}

{********** Begin WHookDef.dpr **************}

{ Interface unit for use with WINHOOK.DLL }

unit WHookDef;

interface

uses
  Windows;

function SetHook(WinHandle: HWND; MsgToSend: Integer): Boolean; stdcall;
function FreeHook: Boolean; stdcall;

implementation

function SetHook; external 'WINHOOK.DLL' Index 1;
function FreeHook; external 'WINHOOK.DLL' Index 2;

end.

{********** End WHookDef.dpr **************}


 {********** Begin Winhook.dpr **************}

 { The project file }

 { WINHOOK.dll }
 library Winhook;

 uses
   WHookInt in 'Whookint.pas';

 exports
   SetHook index 1,
   FreeHook index 2;
 end.

 {********** End Winhook.dpr **************}


WHookInt.pas[править | править код]

{********** Begin WHookInt.pas **************}

unit WHookInt;

interface

uses
  Windows, Messages, SysUtils;

function SetHook(WinHandle: HWND; MsgToSend: Integer): Boolean; stdcall; export;
function FreeHook: Boolean; stdcall; export;
function MsgFilterFunc(Code: Integer; wParam, lParam: Longint): Longint stdcall; export;

implementation


// Memory map file stuff

{ The CreateFileMapping function creates unnamed file-mapping object
  for the specified file. }
function CreateMMF(Name: string; Size: Integer): THandle;
begin
  Result := CreateFileMapping($FFFFFFFF, nil, PAGE_READWRITE, 0, Size, PChar(Name));
  if Result <> 0 then
  begin
    if GetLastError = ERROR_ALREADY_EXISTS then
    begin
      CloseHandle(Result);
      Result := 0;
    end;
  end;
end;

{ The OpenFileMapping function opens a named file-mapping object. }
function OpenMMF(Name: string): THandle;
begin
  Result := OpenFileMapping(FILE_MAP_ALL_ACCESS, False, PChar(Name));
  // The return value is an open handle to the specified file-mapping object.
end;

{ The MapViewOfFile function maps a view of a file into
  the address space of the calling process. }
function MapMMF(MMFHandle: THandle): Pointer;
begin
  Result := MapViewOfFile(MMFHandle, FILE_MAP_ALL_ACCESS, 0, 0, 0);
end;

{ The UnmapViewOfFile function unmaps a mapped view of a file
  from the calling process's address space. }
function UnMapMMF(P: Pointer): Boolean;
begin
  Result := UnmapViewOfFile(P);
end;

function CloseMMF(MMFHandle: THandle): Boolean;
begin
  Result := CloseHandle(MMFHandle);
end;


// Actual hook stuff

type
  TPMsg = ^TMsg;

const
  VK_D = $44;
  VK_E = $45;
  VK_F = $46;
  VK_M = $4D;
  VK_R = $52;

  MMFName = 'MsgFilterHookDemo';

type
  PMMFData = ^TMMFData;
  TMMFData = record
    NextHook: HHOOK;
    WinHandle: HWND;
    MsgToSend: Integer;
  end;

// global variables, only valid in the process which installs the hook.
var
  MMFHandle: THandle;
  MMFData: PMMFData;

function UnMapAndCloseMMF: Boolean;
begin
  Result := False;
  if UnMapMMF(MMFData) then
  begin
    MMFData := nil;
    if CloseMMF(MMFHandle) then
    begin
      MMFHandle := 0;
      Result := True;
    end;
  end;
end;

{ The SetWindowsHookEx function installs an application-defined
  hook procedure into a hook chain.

  WH_GETMESSAGE Installs a hook procedure that monitors messages
  posted to a message queue.
  For more information, see the GetMsgProc hook procedure. }
function SetHook(WinHandle: HWND; MsgToSend: Integer): Boolean; stdcall;
begin
  Result := False;
  if (MMFData = nil) and (MMFHandle = 0) then
  begin
    MMFHandle := CreateMMF(MMFName, SizeOf(TMMFData));
    if MMFHandle <> 0 then
    begin
      MMFData := MapMMF(MMFHandle);
      if MMFData <> nil then
      begin
        MMFData.WinHandle := WinHandle;
        MMFData.MsgToSend := MsgToSend;
        MMFData.NextHook := SetWindowsHookEx(WH_GETMESSAGE, MsgFilterFunc, HInstance, 0);

        if MMFData.NextHook = 0 then
          UnMapAndCloseMMF
        else
          Result := True;
      end
      else
      begin
        CloseMMF(MMFHandle);
        MMFHandle := 0;
      end;
    end;
  end;
end;


{ The UnhookWindowsHookEx function removes the hook procedure installed
  in a hook chain by the SetWindowsHookEx function. }
function FreeHook: Boolean; stdcall;
begin
  Result := False;
  if (MMFData <> nil) and (MMFHandle <> 0) then
    if UnHookWindowsHookEx(MMFData^.NextHook) then
      Result := UnMapAndCloseMMF;
end;



(*
    GetMsgProc(
    nCode: Integer;  {the hook code}
    wParam: WPARAM;  {message removal flag}
    lParam: LPARAM  {a pointer to a TMsg structure}
    ): LRESULT;  {this function should always return zero}

    { See help on ==> GetMsgProc}
*)

function MsgFilterFunc(Code: Integer; wParam, lParam: Longint): Longint;
var
  MMFHandle: THandle;
  MMFData: PMMFData;
  Kill: boolean;
begin
  Result := 0;
  MMFHandle := OpenMMF(MMFName);
  if MMFHandle <> 0 then
  begin
    MMFData := MapMMF(MMFHandle);
    if MMFData <> nil then
    begin
      if (Code < 0) or (wParam = PM_NOREMOVE) then
        { The CallNextHookEx function passes the hook information to the
          next hook procedure in the current hook chain. }
        Result := CallNextHookEx(MMFData.NextHook, Code, wParam, lParam)
      else
      begin
        Kill := False;

        { Examples }
        with TMsg(Pointer(lParam)^) do
        begin
          // Kill Numbers
          if (wParam >= 48) and (wParam <= 57) then Kill := True;
          // Kill Tabulator
          if (wParam = VK_TAB) then Kill := True;
        end;

        { Example to disable all the start-Key combinations }
        case TPMsg(lParam)^.message of
          WM_SYSCOMMAND: // The Win Start Key (or Ctrl+ESC)
            if TPMsg(lParam)^.wParam = SC_TASKLIST then Kill := True;

          WM_HOTKEY:
            case ((TPMsg(lParam)^.lParam and $00FF0000) shr 16) of
              VK_D,      // Win+D        ==> Desktop
              VK_E,      // Win+E        ==> Explorer
              VK_F,      // Win+F+(Ctrl) ==> Find:All (and Find: Computer)
              VK_M,      // Win+M        ==> Minimize all
              VK_R,      // Win+R        ==> Run program.
              VK_F1,     // Win+F1       ==> Windows Help
              VK_PAUSE:  // Win+Pause    ==> Windows system properties
                Kill := True;
            end;
        end;
        if Kill then TPMsg(lParam)^.message := WM_NULL;
        Result := CallNextHookEx(MMFData.NextHook, Code, wParam, lParam)
      end;
      UnMapMMF(MMFData);
    end;
    CloseMMF(MMFHandle);
  end;
end;


initialization
  begin
    MMFHandle := 0;
    MMFData   := nil;
  end;

finalization
  FreeHook;
end.

{********** End WHookInt.pas **************}


HostApp.dpr[править | править код]

{ *******************************************}
{ ***************** Demo   ******************}
{ *******************************************}

{

** HostApp.Exe **
HostApp.dpr
       |-----FrmMainU.pas

}

{********** Begin HostApp.dpr **************}

{ Project file }

program HostApp;

uses
  Forms,
  FrmMainU in 'FrmMainU.pas' {FrmMain};

{$R *.RES}

begin
  Application.Initialize;
  Application.CreateForm(TFrmMain, FrmMain);
  Application.Run;
end.

{********** End HostApp.dpr **************}

FrmMainU.pas[править | править код]

{********** Begin FrmMainU.pas **************}

unit FrmMainU;

interface

uses
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
  StdCtrls, ExtCtrls;

const
  HookDemo = 'WINHOOK.dll';

const
  WM_HOOKCREATE = WM_USER + 300;

type
  TFrmMain = class(TForm)
    Panel1: TPanel;
    BtnSetHook: TButton;
    BtnClearHook: TButton;
    procedure BtnSetHookClick(Sender: TObject);
    procedure BtnClearHookClick(Sender: TObject);
    procedure FormCreate(Sender: TObject);
  private
    FHookSet: Boolean;
    procedure EnableButtons;
  public

  end;

var
  FrmMain: TFrmMain;

function SetHook(WinHandle: HWND; MsgToSend: Integer): Boolean; stdcall;
  external HookDemo;

function FreeHook: Boolean; stdcall; external HookDemo;

implementation

{$R *.DFM}

procedure TFrmMain.EnableButtons;
begin
  BtnSetHook.Enabled   := not FHookSet;
  BtnClearHook.Enabled := FHookSet;
end;

// Start the Hook
procedure TFrmMain.BtnSetHookClick(Sender: TObject);
begin
  FHookSet := LongBool(SetHook(Handle, WM_HOOKCREATE));
  EnableButtons;
end;

// Stop the Hook
procedure TFrmMain.BtnClearHookClick(Sender: TObject);
begin
  FHookSet := FreeHook;
  EnableButtons;
  BtnClearHook.Enabled := False;
end;

procedure TFrmMain.FormCreate(Sender: TObject);
begin
  EnableButtons;
end;

end.

{********** End FrmMainU.pas **************}


Source: Взято с сайта: http://www.swissdelphicenter.ch
ID: 02226