如何使得OCX控件能响应PreTranslateMessage消息？

1、首先在OCX的CPP文件中声明一个全局变量：

static HHOOK hHook = NULL;

2、定义VHook处理函数：

LRESULT CALLBACK GetMessageProc(int nCode, WPARAM wParam, LPARAM lParam)

{

// Switch the module state for the correct handle to be used.

AFX_MANAGE_STATE(AfxGetStaticModuleState( ));

// If this is a keystrokes message, translate it in controls'

// PreTranslateMessage().

LPMSG lpMsg = (LPMSG) lParam;

if( (nCode >= 0) && (PM_REMOVE == wParam) &&

AfxGetApp()->PreTranslateMessage(lpMsg))

{

lpMsg->message = WM_NULL;

lpMsg->lParam = 0L;

lpMsg->wParam = 0;

}

// Passes the hook information to the next hook procedure in

// the current hook chain.

return ::CallNextHookEx(hHook, nCode, wParam, lParam);

}

3、在OCX的“OnCreate”中添加如下代码：

// Because ActiveX control is an inproc server, it does not have a

// message pump. So, messages to child windows created by the

// ActiveX control are not going to be received by the control.

// Thus, we set up a message hook to call PreTranslateMessage().

// This results in the call to FilterToolTipMessage(), which

// activates tooltips.

hHook = ::SetWindowsHookEx(WH_GETMESSAGE, GetMessageProc, 

AfxGetInstanceHandle(),GetCurrentThreadId());

4、释放资源，在OCX的“OnDestroy”消息中添加如下代码：

    VERIFY(::UnhookWindowsHookEx(hHook));

参考：

http://support.microsoft.com/kb/233263/en-us/

http://support.microsoft.com/kb/168777/en-us/