SetWindowsHookEx() function cannot trap Alt-Tab messages

[JP Manalo]

I have read the API on how to use the SetWindowsHookEx() function and I was able to interrupt other keyboard keypresses in Windows 98 but I still can't trap Alt-Tab. Thank you.

[Marc Soleda]

To trap Alt+Tab you have to catch the message before the OS process it. A simple way to achieve it is to register Alt+Tab as a hotkey: BOOL CYourDlg::OnInitDialog() {    ...    m_nHotKeyID = 100; // Unique identifier of the new hotkey.    BOOL m_isKeyRegistered = RegisterHotKey(GetSafeHwnd(), m_nHotKeyID, MOD_ALT, VK_TAB);    ... } To process the hotkey PreTranslate WM_HOTKEY: BOOL CYourDlg::PreTranslateMessage(MSG* pMsg) {    ...    if((pMsg->message == WM_HOTKEY) &&      (pMsg->wParam == m_nHotKeyID))       MessageBox("Alt+Tab trapped");    .... } Remember to unregister it before existing the app: BOOL CYourDlg::OnDestroy() {    ...    UnregisterHotKey(GetSafeHwnd(), m_nHotKeyID);    ... } Read Lock Windows Desktop[^], there are some references that shows it. I hope it helps, Marc Soleda. ... she said you are the perfect stranger she said baby let's keep it like this... Tunnel of Love, Dire Straits.