#include <afxwin.h>
// #include <windows.h>
 
class CKeybHookApp : public CWinApp
{
public:
    CKeybHookApp();
    DECLARE_MESSAGE_MAP()
} theApp;


LRESULT CALLBACK LaunchHook(int nCode,WPARAM wParam,LPARAM lParam);
HHOOK kbHook;

// #define pCW ((CWPSTRUCT*)lParam)

LRESULT CALLBACK LaunchHook(int nCode,WPARAM wParam,LPARAM lParam)
{
    // 让其它全局钩子获得消息.
    LRESULT Result=CallNextHookEx(kbHook,nCode,wParam,lParam);
    if(nCode==HC_ACTION)
    {  
        LPCTSTR info = NULL;    
        if( (lParam & WM_KEYDOWN) == WM_KEYDOWN)
        {
            info = "key dn";
        }
        else if( (lParam & WM_KEYUP) == WM_KEYUP)
        {
            info = "key up";
        }
        else if( (lParam & WM_SYSKEYDOWN) == WM_SYSKEYDOWN)
        {
            info = "sys key down";
        }
        else ( (lParam & WM_SYSKEYUP) == WM_SYSKEYUP )
        {  // 40 行？？？
            info = "sys key up";
        }
        MessageBox(NULL,info,"win",MB_OK);
    }
    
    return Result;
}

int main (void)
{
    kbHook=(HHOOK)SetWindowsHookEx(WH_KEYBOARD,
        (HOOKPROC)LaunchHook, theApp.m_hInstance, 0 );

    if( kbHook==NULL ) {
        MessageBox(NULL,"error SetWindowsHookEx","win",MB_OK);
        return 0;
    }
        
    // 消息循环是必须的，想知道原因可以查msdn
    MSG msg;
    while (GetMessage (&msg, NULL, 0, 0))
    {
        TranslateMessage (&msg);
        DispatchMessage (&msg);
    };

    UnhookWindowsHookEx (kbHook);
    return 0;
};
为什么这个程序提示：
dd1.cpp(40) : error C2143: syntax error : missing ';' before '{'
感觉花括号已经匹配了啊？？

那句话少了if,条件判断不加if的吗?

else ( (lParam & WM_SYSKEYUP) == WM_SYSKEYUP )
要加if

if（）
else if
else
这种格式有问题？？

没问题，可是你的else后面又有条件所以还是要加if

恩 ，是呀！！
谢谢啦