2023年12月7日发(作者：)

c++钩子函数

结合自定义消息映射方面,作为学习的一个总结.

Step1:创建win32动态链接库(an empty project DLL),命名为HookDLL

1:增加一个类,命名为

2:增加头文件

#include

#include "DLL.h"

3:创建全局变量

#pragma data_seg("Shared")

HHOOK mHook=NULL;

HINSTANCE hInstance=NULL;

#pragma data_seg()

4:在中增加实现几个函数

a.钩子回调函数 LRESULT WINAPI KeyProc(int code,WPARAM wParam,LPARAM lParam)

b. 入口函数

BOOL APIENTRY DllMain( HANDLE hModule,

DWORD ul_reason_for_call,

LPVOID lpReserved)

c. 供外界调用的启动与停止钩子函数

extern "C" __declspec(dllexport) BOOL WINAPI Start()

extern "C" __declspec(dllexport) void WINAPI Stop()

d.自定义消息:#define WM_Hook WM_USER+100

具体代码如下:

LRESULT WINAPI KeyProc(int code,WPARAM wParam,LPARAM lParam)

if(code==HC_ACTION && (lParam & 0xc000ffff) ==1)

char *sName;

BOOL b_sft=::GetAsyncKeyState (VK_SHIFT)>>((sizeof(short)*8)-1);

if(b_sft)

switch(wParam)

{

case '1':sName="!"; break;

case '2':sName="@"; break;case '3':sName = "#";break;case '4':sName = "$";break;case '5':sName = "%";break;case '6':sName = "^";break;case '7':sName = "&";break;case '8':sName = "*";break;case '9':sName = "(";break;case '0':sName = ")";break;case 'A':sName = "A";break;case 'B':sName = "B";break;case 'C':sName = "C";break;case 'D':sName = "D";break;case 'E':sName = "E";break;case 'F':sName = "F";break;case 'G':sName = "G";break;case 'H':sName = "H";break;case 'I':sName = "I";break;case 'J':sName = "J";break;case 'K':sName = "K";break;case 'L':sName = "L";break;case 'M':sName = "M";break;case 'N':sName = "N";break;case 'O':sName = "O";break;case 'P':sName = "P";break;case 'Q':sName = "Q";break;case 'R':sName = "R";break;case 'S':sName = "S";break;case 'T':sName = "T";break;case 'U':sName = "U";break;case 'V':sName = "V";break;case 'W':sName = "W";break;case 'X':sName = "X";break;case 'Y':sName = "Y";break;case 'Z':sName = "Z";break;}elseswitch(wParam){/*0~9*/case '1': sName="1"; break;case '2':sName = "2";break;case '3':sName = "3";break;case '4':sName = "4";break;case '5':sName = "5";break;case '6':sName = "6";break;case '7':sName = "7";break;case '8':sName = "8";break;case '9':sName = "9";break;case '0':sName = "0";break;/*A~Z*/case 'A':sName = "a";break;case 'B':sName = "b";break;case 'C':sName = "c";break;case 'D':sName = "d";break;case 'E':sName = "e";break;case 'F':sName = "f";break;case 'G':sName = "g";break;case 'H':sName = "h";break;case 'I':sName = "i";break;case 'J':sName = "j";break;case 'K':sName = "k";break;case 'L':sName = "l";break;case 'M':sName = "m";break;case 'N':sName = "n";break;case 'O':sName = "o";break;case 'P':sName = "p";break;case 'Q':sName = "q";break;case 'R':sName = "r";break;case 'S':sName = "s";break;case 'T':sName = "t";break;case 'U':sName = "u";break;case 'V':sName = "v";break;case 'W':sName = "w";break;case 'X':sName = "x";break;case 'Y':sName = "y";break;case 'Z':sName = "z";break;}switch(wParam) //数字键case VK_BACK:sName="~"; break;case VK_NUMPAD1:sName="1";break;case VK_NUMPAD3:sName = "3";break;case VK_NUMPAD4:sName = "4";break;case VK_NUMPAD5:sName = "5";break;case VK_NUMPAD6:sName = "6";break;case VK_NUMPAD7:sName = "7";break;case VK_NUMPAD8:sName = "8";break;case VK_NUMPAD9:sName = "9";break;case VK_NUMPAD0:sName = "0";break;case VK_MULTIPLY:sName = "*";break;case VK_ADD:sName="+";break;case VK_SUBTRACT:sName="-";break;case VK_DECIMAL:sName=".";break;case VK_DIVIDE:sName="/";break;HWND H_wnd=::GetForegroundWindow ();//自定义消息发送

::SendMessage (H_wnd,WM_Hook,wParam, (LPARAM)(LPCSTR)sName);

MessageBox(H_wnd,sName,"键盘提示",MB_OK);

return CallNextHookEx( mHook, code, wParam, lParam );

BOOL APIENTRY DllMain(HANDLE hModule,

DWORD ul_reason_for_call,

LPVOID lpReserved)

switch(ul_reason_for_call)

{

case DLL_PROCESS_ATTACH:

hInstance=(HINSTANCE)hModule;

break;

case DLL_THREAD_ATTACH:

case DLL_THREAD_DETACH:

case DLL_PROCESS_DETACH:

break;

}

return TRUE;

extern "C" __declspec(dllexport) BOOL WINAPI Start()

if(mHook!=NULL) return FALSE;

//WH_KEYBOARD值为2,键盘消息钩子

//KeyProc 为回调函数

//hInstance:实例

//0:表示全局钩子

mHook=::SetWindowsHookEx (WH_KEYBOARD,KeyProc,hInstance,0);

return mHook!=NULL;

extern "C" __declspec(dllexport) void WINAPI Stop()

//要卸载的钩子

::UnhookWindowsHookEx (mHook);

5.在DLL.h中加入如下函数定义

extern "C" __declspec(dllexport) BOOL WINAPI Start();

extern "C" __declspec(dllexport) void WINAPI Stop();

编译生成和

Step 2:1.新建MFC基本对话框应用程序,命名为HookTest,在其工作目录加入和

2.在中加入如下引用

//加入动态链接库的引用

#include "DLL.h"

//隐式调用库文件

#pragma comment(lib,"HookDLL")

3.加入自定义消息

#define WM_Hook WM_USER+100

4.加入消息映射

BEGIN_MESSAGE_MAP(CHookTestDlg, CDialog) ON_MESSAGE(WM_Hook,OnReceive) //增加部分END_MESSAGE_MAP()

5.在CHookTestDlg.h中加入消息声明

afx_msg void OnReceive(WPARAM wParam,LPARAM lParam);

6.在对话框另加入两个按钮btnStart,btnStop,相应的代码为:

void CHookTestDlg::OnbtnStartHook()

// TODO: Add your control notification handler code here

Start();

void CHookTestDlg::OnbtnStopHook()

// TODO: Add your control notification handler code here

Stop();

7.增加映射函数OnReceive的实现代码

void CHookTestDlg::OnReceive (WPARAM wParam,LPARAM lParam){ CEdit * mEdit=(CEdit *)GetDlgItem(IDC_EDIT1); mEdit-

>SetWindowText ((LPCSTR)lParam); }

Step 3:

运行程序,点btnStart,按键盘上任意键如A,,将弹出一对话框,并且文本显示回传的A