大家好，又见面了，我是你们的朋友全栈君。
// CatchKey.cpp : Defines the entry point for the DLL application.
//
#define _WIN32_WINNT 0x0500 //设置系统版本，可以使用底层键盘钩子
#define WM_MY_SHORTS (WM_USER + 105)
#include “windows.h”
//全局变量
LPWORDg_lpdwVirtualKey = NULL; //Keycode 数组的指针
int g_nLength = 0; //Keycode 数组的大小
HINSTANCE g_hInstance = NULL; //模块实例句柄
HHOOK g_hHook = NULL; //钩子句柄
HWND g_hWnd = NULL;
BOOL APIENTRY DllMain(HANDLE hModule, DWORD ul_reason_for_call,LPVOID lpReserved)
{
//保存模块实例句柄
g_hInstance = (HINSTANCE)hModule;
//在进程结束或线程结束时卸载钩子
switch (ul_reason_for_call)
{
case DLL_PROCESS_ATTACH:
break;
case DLL_THREAD_ATTACH:
break;
case DLL_PROCESS_DETACH:
case DLL_THREAD_DETACH:
delete g_lpdwVirtualKey;
if (g_hHook != NULL) UnhookWindowsHookEx(g_hHook);
break;
}
return TRUE;
}
LRESULT CALLBACK LowLevelKeyboardProc(int nCode, WPARAM wParam,LPARAM lParam)
{
//判断是否是有效按键
if (nCode >= HC_ACTION && wParam==WM_KEYDOWN)
{
BOOL bctrl = GetAsyncKeyState(VK_CONTROL)>>((sizeof(SHORT) *8)-1);
KBDLLHOOKSTRUCT* pStruct = (KBDLLHOOKSTRUCT*)lParam;
LPWORD tmpVirtualKey = g_lpdwVirtualKey;
if (pStruct->vkCode == 80 && bctrl)
PostMessage(g_hWnd,WM_MY_SHORTS,0,1);
return TRUE;
}
//传给系统中的下一个钩子
return CallNextHookEx(g_hHook, nCode, wParam, lParam);
}
_declspec(dllexport)
BOOL WINAPI StartCatch(LPWORD lpdwVirtualKey, int nLength, HWND pWnd)
{
g_hWnd = pWnd;
//如果已经安装键盘钩子则返回 FALSE
if (g_hHook != NULL) return FALSE;
//将用户传来的 keycode 数组保存在全局变量中
g_lpdwVirtualKey = (LPWORD)malloc(sizeof(WORD) * nLength);
LPWORD tmpVirtualKey = g_lpdwVirtualKey;
for (int i = 0; i < nLength; i++)
{
*tmpVirtualKey++ = *lpdwVirtualKey++;
}
g_nLength = nLength;
//安装底层键盘钩子
g_hHook = SetWindowsHookEx(WH_KEYBOARD_LL, LowLevelKeyboardProc, g_hInstance, NULL);
if (g_hHook == NULL) return FALSE;
return TRUE;
}
_declspec(dllexport)
BOOL WINAPI StopCatch()
{ //卸载钩子
if (UnhookWindowsHookEx(g_hHook) == 0) return FALSE;
g_hHook = NULL;
return TRUE;
}
利用底层的键盘钩子
LRESULT CALLBACK LowLevelKeyboardProc(int nCode, WPARAM wParam,LPARAM lParam)来拦截 按键的时候
键盘的键按下和弹起时候会发生WM_KEYUP 和
WM_KEYDOWN两个消息，
这两个消息都会被hook，所以如此。
所以需要对 wParam 进行判断 是 WM_KEYDOWN 还是 WM_KEYUP
发布者：全栈程序员-站长，转载请注明出处：https://javaforall.net/132954.html原文链接：https://javaforall.net
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