Windows键盘钩子

Runtime：VS2013

#include "stdafx.h"
#include <windows.h>
#include <conio.h>

DWORD g_main_tid = 0;
HHOOK g_kb_hook = 0;

bool CALLBACK con_handler(DWORD CtrlType)
{
    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;
    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 [%04x], scanCode [%04x]
",
        info, p->vkCode, p->scanCode);
    // always call next hook
    return CallNextHookEx(g_kb_hook, code, w, l);
};

DWORD WINAPI KbHookThread(LPVOID lpParam)
{
    g_main_tid = GetCurrentThreadId();

    //register Ctrl+C callback
    SetConsoleCtrlHandler((PHANDLER_ROUTINE)&con_handler, TRUE);
    g_kb_hook = SetWindowsHookEx(WH_KEYBOARD_LL, //Installs a hook procedure that monitors low-level keyboard input events
        (HOOKPROC)&kb_proc, //A hook procedure that monitors low-level keyboard input events
        NULL,//A handle to the DLL containing the hook procedure pointed to by the lpfn parameter. The hMod parameter must be set to NULL if the dwThreadId parameter specifies a thread created by the current process and if the hook procedure is within the code associated with the current process.(GetModuleHandle(NULL))
        0);//The identifier of the thread with which the hook procedure is to be associated. For desktop apps, if this parameter is zero, the hook procedure is associated with all existing threads running in the same desktop as the calling thread. For Windows Store apps, see the Remarks section.
    if (g_kb_hook == NULL) {
        printf("SetWindowsHookEx failed, %ld
", GetLastError());
        return 0;
    }

    // Message loop
    MSG msg;
    

    //If GetMessage retrieves the WM_QUIT message, the return value is zero.
    while (GetMessage(&msg, NULL, 0, 0)) {
        TranslateMessage(&msg);
        DispatchMessage(&msg);
    }
    
    //exit the thread
    UnhookWindowsHookEx(g_kb_hook);
    return 0;
};

int _tmain(int argc, _TCHAR* argv[])
{
    HANDLE h = CreateThread(NULL, 0, KbHookThread, NULL, 0, NULL);
    if (NULL == h) {
        printf("CreateThread failed, %ld
", GetLastError());
        return -1;
    }

    //wait thread to exit
    WaitForMultipleObjects(1, &h, TRUE, INFINITE);

    return 0;
}