EnumChildWindows Function

最新推荐文章于 2023-10-30 09:45:50 发布

原创最新推荐文章于 2023-10-30 09:45:50 发布 · 167 阅读

0 ·

CC 4.0 BY-SA版权

本文介绍如何使用EnumChildWindows函数枚举指定父窗口的所有子窗口，并通过回调函数SendPrepareToClose执行子窗口的清理工作。清理过程涉及递归地处理所有子窗口及其子代。

The EnumChildWindows function enumerates the child windows that belong to the specified parent window by passing the handle to each child window, in turn, to an application-defined callback function. EnumChildWindows continues until the last child window is enumerated or the callback function returns FALSE.

主框架调用EnumChildWindows让每个子窗口都去执行SendPrepareToClose去做每个子窗口的清理工作。

BOOL CMainFrame::DestroyWindow()
{
::EnumChildWindows(m_hWnd, SendPrepareToClose, 0);

return CMDIFrameWnd::DestroyWindow();
}

static BOOL CALLBACK SendPrepareToClose(HWND hWnd, LPARAM)
{
    CWnd* pWnd = CWnd::FromHandlePermanent(hWnd);
    if (pWnd != NULL)
    {
        pWnd->SendMessage(WM_USER_PREPARE_TO_CLOSE);
        if (pWnd->GetWindow(GW_CHILD) != NULL)
            ::EnumChildWindows(pWnd->m_hWnd, SendPrepareToClose, 0);
    }
    return TRUE;
}