MFC ACTIVEX 全屏

HWND m_hWndParent;
BOOL m_fullscreen;
void CDialog::SwitchFullScreen(void)
{
    LONG style = ::GetWindowLong(this->m_hWnd, GWL_STYLE);
    if (m_fullscreen == false)
    {
        //隐藏系统任务栏
        CWnd * wnd = FindWindow("Shell_TrayWnd",NULL);
        wnd->SetWindowPos(NULL, 0, 0, 0, 0, SWP_HIDEWINDOW);
        m_hWndParent = ::GetParent(m_hWnd);
        ::ShowWindow(m_hWndParent, SW_HIDE);
        ::SetParent(m_hWnd, NULL);
        style &= ~(WS_DLGFRAME | WS_THICKFRAME);
        SetWindowLong(this->m_hWnd,GWL_STYLE, style);
        this->ShowWindow(SW_SHOWMAXIMIZED);
        int cx = ::GetSystemMetrics(SM_CXSCREEN);
        int cy = ::GetSystemMetrics(SM_CYSCREEN);
        MoveWindow(0, 0, cx, cy, TRUE);
    }
    else
    {
        //显示系统任务栏
        CWnd * wnd = FindWindow("Shell_TrayWnd",NULL);
        wnd->SetWindowPos(NULL,0,0,0,0,SWP_SHOWWINDOW);
        style |= WS_DLGFRAME | WS_THICKFRAME;
        SetWindowLong(this->m_hWnd, GWL_STYLE, style);
        ::SetParent(m_hWnd, m_hWndParent);
        ::ShowWindow(m_hWndParent, SW_SHOW);
    }
    m_fullscreen = !m_fullscreen;
}