Hook GetMessage
Hook GetMessage
代码
unit Unit1;
interface
uses
Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
StdCtrls;
const
WM_TestMessage = WM_USER + 2000;
type
TForm1 = class(TForm)
Button1: TButton;
procedure FormCreate(Sender: TObject);
procedure Button1Click(Sender: TObject);
procedure FormDestroy(Sender: TObject);
private
{ Private declarations }
public
{ Public declarations }
end;
var
Form1: TForm1;
implementation
{$R *.DFM}
var
HookHandle: HHOOK;
function TestHookProc(Code: Integer; WParam: Longint;Msg:Longint): Longint;stdcall;
begin
if (Code = HC_ACTION) then
if PMsg(Msg)^.Message = WM_TestMessage then
begin
showMessage('已经截获该消息');
end;
Result := CallNextHookEx(HookHandle, Code, WParam, Longint(@Msg));
end;
procedure TForm1.FormCreate(Sender: TObject);
begin
HookHandle:=SetWindowsHookEx(WH_GETMESSAGE,@TestHookProc,0,GetCurrentThreadID);
end;
procedure TForm1.FormDestroy(Sender: TObject);
begin
UnhookWindowsHookEx(HookHandle);
end;
procedure TForm1.Button1Click(Sender: TObject);
begin
PostMessage(self.Handle,WM_TestMessage,0,0);
//SendMessage(self.Handle,WM_TestMessage,0,0);
//这里用SendMessage是不行的,具体见相关资料
end;
end.
Catch ESC Key
代码
var
Form1: TForm1;
HookHandle:HHook;
const
WM_TestMessage = WM_USER + 2000;
implementation
{$R *.dfm}
function TestHookProc(Code:Integer;WParam:Longint;LParam:Longint):Longint;stdcall;
begin
if PMsg(LParam)^.Message = WM_KEYDOWN then
if PMsg(LParam)^.wParam = VK_ESCAPE then
begin
Showmessage('ESC Key Down!');
Form1.Close;
end;
Result:=CallNextHookEx(HookHandle,Code,WParam,Longint(@LParam));
end;
procedure TForm1.FormCreate(Sender: TObject);
begin
HookHandle:=SetWindowsHookEx(WH_GETMESSAGE,TestHookProc,0,GetCurrentThreadID);
end;
procedure TForm1.FormDestroy(Sender: TObject);
begin
UnHookWindowsHookEx(HookHandle);
end;