原程式碼裡用的hook type是WH_JOURNALRECORD，而當其callback function的code是HC_ACTION時lParam 是指向一個EVENTMSG Structure，而這個結構體中才有posted window的handle欄位。

typedef struct {
UINT message;
UINT paramL;
UINT paramH;
DWORD time;
HWND hwnd;
} EVENTMSG, *PEVENTMSG;

關於我之前提的用EVENTMSG->hwnd得知是哪個window post的，經我自己測式發現，當WM_KEYDOWN時是無效的，但若是WM_LBUTTONDOWN時就有效。也不知是為何…可用下面的程式測看看。

#define _WIN32_WINNT 0x0400
#define STRICT
#define WIN32_LEAN_AND_MEAN

#include
#include
#include

DWORD g_main_tid = 0;
HHOOK g_kb_hook = 0;

BOOL CALLBACK con_handler(DWORD dwCtrlType)
{
PostThreadMessage (g_main_tid, WM_QUIT, 0, 0);
return TRUE;
}

LRESULT CALLBACK kb_proc (int code, WPARAM w, LPARAM l)
{
BYTE szKeyState[256];
UINT uScanCode;
unsigned short szAscii[32] = {0};
char szTitle[256] = {0};

/*
PKBDLLHOOKSTRUCT p = (PKBDLLHOOKSTRUCT)l;
const char *info = NULL;

if (w == WM_KEYDOWN)
info = "key dn";
else if (w == WM_KEYUP)
info = "key up";
else if (w == WM_SYSKEYDOWN)
info = "sys key dn";
else if (w == WM_SYSKEYUP)
info = "sys key up";
printf ("%s, vkCode [%c], scanCode [x] \n", info, p->vkCode, p->scanCode);
*/

if(code == HC_ACTION)
{
EVENTMSG *emsg = (EVENTMSG*)l;
if(emsg->message == WM_KEYDOWN)
// if(emsg->message == WM_LBUTTONDOWN) EVENTMSG->hwnd only work here
{

char szTitle[256] = {0};
GetWindowText(GetForegroundWindow(),szTitle,255);

GetKeyboardState(szKeyState);
GetKeyState(VK_SHIFT);
__asm
{
//mov szKeyState[VK_SHIFT*TYPE BYTE], al ; scaled
mov szKeyState[VK_SHIFT], al //not scaled but the type is BYTE so it's OK here
mov eax, emsg
mov ecx, [eax].paramH
shr ecx, 16
mov uScanCode, ecx
}
ToAscii(emsg->paramL,uScanCode,szKeyState,szAscii,0);
//GetWindowText(emsg->hwnd,szTitle,255);
printf("vkCode = %s from title = %s \n",szAscii,szTitle);
// printf("vkCode = %s from title = %d \n",szAscii,emsg->hwnd);

}
}
// always call next hook
return CallNextHookEx (g_kb_hook, code, w, l);
}

int main (void)
{
MSG msg;
g_main_tid = GetCurrentThreadId ();
SetConsoleCtrlHandler(&con_handler, TRUE);

// g_kb_hook = SetWindowsHookEx (WH_KEYBOARD_LL, &kb_proc,GetModuleHandle (NULL),0);
g_kb_hook = SetWindowsHookEx (WH_JOURNALRECORD, &kb_proc,GetModuleHandle (NULL),0);
if (g_kb_hook == NULL)
{
fprintf (stderr, "SetWindowsHookEx failed with error %d\n",::GetLastError());
return 0;
}

while (GetMessage (&msg, NULL, 0, 0))
{
TranslateMessage (&msg);
DispatchMessage (&msg);
}
UnhookWindowsHookEx (g_kb_hook);
return 0;
}

我最後用了你的hook type =WH_KEYBOARD_LL，加裝了GetForegroundWindow()來模擬你要的結果，但應該不完善。不過我也沒有其他的辦法了…

#define _WIN32_WINNT 0x0400
#define STRICT
#define WIN32_LEAN_AND_MEAN

#include
#include
#include

DWORD g_main_tid = 0;
HHOOK g_kb_hook = 0;
BOOL CALLBACK con_handler (DWORD)
{
PostThreadMessage (g_main_tid, WM_QUIT, 0, 0);
return TRUE;
};

LRESULT CALLBACK kb_proc (int code, WPARAM w, LPARAM l)
{

PKBDLLHOOKSTRUCT p = (PKBDLLHOOKSTRUCT)l;
const char *info = NULL;

/************************************************************************/
/* Below is add by Xiao Chong */
/************************************************************************/

char szTitle[256] = {0};

GetWindowText(GetForegroundWindow(),szTitle,255);

/************************************************************************/
/* End Modify */
/************************************************************************/

if (w == WM_KEYDOWN)
info = "key dn";
else if (w == WM_KEYUP)
info = "key up";
else if (w == WM_SYSKEYDOWN)
info = "sys key dn";
else if (w == WM_SYSKEYUP)
info = "sys key up";
printf ("%s, vkCode [%c], scanCode [x],title = %s \n", info, p->vkCode, p->scanCode,szTitle); //modified by Xiao Chong

// always call next hook
return CallNextHookEx (g_kb_hook, code, w, l);
}

int main (void)
{
g_main_tid = GetCurrentThreadId ();
SetConsoleCtrlHandler(&con_handler, TRUE);
g_kb_hook = SetWindowsHookEx (WH_KEYBOARD_LL, &kb_proc,GetModuleHandle (NULL),0);
if (g_kb_hook == NULL)
{
fprintf (stderr, "SetWindowsHookEx failed with error %d\n",::GetLastError());
return 0;
}

MSG msg;
while (GetMessage (&msg, NULL, 0, 0))
{
TranslateMessage (&msg);
DispatchMessage (&msg);
}
UnhookWindowsHookEx (g_kb_hook);
return 0;
}