windowsHOOK消息真心不知道HOOK了些什么和什么

#define _WIN32_WINNT 0x500

#include <windows.h>

static LRESULT CALLBACK hookproc(UINT nCode,WPARAM wParam,LPARAM lParam);

BOOL _stdcall InstallMyHook(HWND hWnd);

BOOL _stdcall UninstallMyHook(HWND hWnd);

HHOOK hook;

HWND hWndMain;

HINSTANCE hInst=GetModuleHandle("MouseDll.dll");

BOOL _stdcall InstallMyHook(HWND hWnd){
hook=SetWindowsHookEx(WH_MOUSE_LL,(HOOKPROC)hookproc,hInst,0);
//SetWindowsHookEx()
if(!hook)
{
DWORD reason=GetLastError();
LPCSTR tt=(LPCSTR)&reason;
//CString str;
// str.Format("%c",reason);
MessageBox(hWnd,tt,"HHOOK",MB_OK);

// OutputDebugString(reason);
return FALSE;
}
hWndMain=hWnd;
return TRUE;

} // HOOK安装

BOOL _stdcall UninstallMyHook(HWND hWnd)

{
if(hWnd != hWndMain || hWnd==NULL)
return FALSE;
BOOL unhooked=UnhookWindowsHookEx(hook);
if(unhooked)
hWndMain=NULL;
return unhooked;

}

static LRESULT CALLBACK hookproc(UINT nCode,WPARAM wParam,LPARAM lParam)

{
if(wParam == WM_MOUSEMOVE)
{
MOUSEHOOKSTRUCT *mhookstruct;
mhookstruct=(MOUSEHOOKSTRUCT*)lParam;
POINT pt=mhookstruct->pt;
PostMessage(hWndMain,WM_MOUSEMOVE,MK_CONTROL,MAKELPARAM(pt.x,pt.y));
}
return CallNextHookEx(hook,nCode,wParam,lParam);

}