使用目录内容建立菜单

目的：根据目录内容，建立一个菜单。菜单项为目录中的文件和子目录（以弹出方式显示）。

解决方案：遍历子目录，建立一个文件路径数组。菜单项的ID是数组的索引。当用户单击某个菜单项时，从数组中读取文件路径并执行相应的操作。

细节：

首先，我们需要一个菜单。新建立的菜单将作为此菜单的子菜单。

CMenu*          pmenuFavorites=new CMenu;
pmenuFavorites->CreatePopupMenu();

然后读取目录，建立菜单

BuildFavoritesMenu(szPath, 0, pmenuFavorites);

最后，将菜单连接到已有菜单上面去

CMenu* pMenu=m_menuPopup.GetSubMenu(0);

pMenu->ModifyMenu(m_iMenuPosition,MF_BYPOSITION|MF_POPUP| MF_STRING,(UINT)(pmenuFavorites->GetSafeHmenu()),_T("动态菜单"));

pmenuFavorites->Detach();
delete pmenuFavorites;


其它的都很简单，但是建立这个菜单很麻烦

申明一个变量来存文件路径

CStringArray m_astrFavoriteURLs;

int CWorkBenchDlg::BuildMenu(LPCTSTR pszPath, int nStartPos, CMenu* pMenu)
{
    CString         strPath(pszPath);//path to start from
    CString         strPath2;//path to start from,with trailing backslash
    CString         str;//menu item text
    WIN32_FIND_DATA wfd;
    HANDLE          h;
    int             nPos;
    int             nEndPos;
    int             nNewEndPos;
    int             nLastDir;
    TCHAR           buf[INTERNET_MAX_PATH_LENGTH];
    CStringArray    astrFavorites;
    CStringArray    astrDirs;
    CMenu*          pSubMenu;

    // make sure there's a trailing backslash
    if(strPath[strPath.GetLength() - 1] != _T('\\'))
        strPath += _T('\\');
    strPath2 = strPath;
    strPath += _T("*.*");

    // now scan the directory, first for files and then for subdirectories
    //make a array of full pathnames.
    h = FindFirstFile(strPath, &wfd);
    if(h != INVALID_HANDLE_VALUE)
    {
        nEndPos = nStartPos;
        do
        {
            if((wfd.dwFileAttributes & (FILE_ATTRIBUTE_DIRECTORY|FILE_ATTRIBUTE_HIDDEN|FILE_ATTRIBUTE_SYSTEM))==0)
            {
                str = wfd.cFileName;//file name
                lstrcpy(buf,strPath2 + str);//file full pathname
                if(str.Right(4) .CompareNoCase(_T(".url"))==0)
                {
                    // an .URL file is formatted just like an .INI file, so we can
                    // use GetPrivateProfileString() to get the information we want

                    //fill the buf with URL
                    ::GetPrivateProfileString(_T("Inte.netShortcut"), _T("URL"),
                                              _T(""), buf, INTERNET_MAX_PATH_LENGTH,
                                              strPath2 + str);
                    str = str.Left(str.GetLength() - 4);//the name of URL

                }
                if(str.Right(4) .CompareNoCase( _T(".lnk"))==0)
                {
                    //fill the buf with link target
                    CGlobal::ResolveShortCut(NULL,strPath2 + str,buf);
                    str = str.Left(str.GetLength() - 4);
                }
                //TODO:add other format process here

                //这里对.url文件和.lnk文件做了处理，去掉了扩展名。lnk文件的处理参见http://support.microsoft.com/support/kb/articles/Q130/6/98.asp 。可以对其他格式的文件进行处理并更改菜单文字。

                // scan through the array and perform an insertion sort
                // to make sure the menu ends up in alphabetic order
                for(nPos = nStartPos ; nPos < nEndPos ; ++nPos)
                {
                    if(str.CompareNoCase(astrFavorites[nPos]) < 0)
                        break;
                }
                astrFavorites.InsertAt(nPos, str);
                m_astrFavoriteURLs.InsertAt(nPos, buf);
                ++nEndPos;
            }
        } while(FindNextFile(h, &wfd));
        FindClose(h);
        // Now add these items to the menu
        for(nPos = nStartPos ; nPos < nEndPos ; ++nPos)
        {
            pMenu->AppendMenu(MF_STRING | MF_ENABLED, 0xe00 + nPos, astrFavorites[nPos]);
        }


        // now that we've got all files, check the subdirectories for more
        nLastDir = 0;
        h = FindFirstFile(strPath, &wfd);
        ASSERT(h != INVALID_HANDLE_VALUE);
        do
        {
            if(wfd.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)
            {
                // ignore the current and parent directory entries
                if(lstrcmp(wfd.cFileName, _T(".")) == 0 || lstrcmp(wfd.cFileName, _T("..")) == 0)
                    continue;

                for(nPos = 0 ; nPos < nLastDir ; ++nPos)
                {
                    if(astrDirs[nPos].CompareNoCase(wfd.cFileName) > 0)
                        break;
                }
                pSubMenu = new CMenu;
                pSubMenu->CreatePopupMenu();

                // call this function recursively.
                nNewEndPos = BuildFavoritesMenu(strPath2 + wfd.cFileName, nEndPos, pSubMenu);
                if(nNewEndPos != nEndPos)
                {
                    // only intert a submenu if there are in fact files in the subdirectory
                    nEndPos = nNewEndPos;
                    pMenu->InsertMenu(nPos, MF_BYPOSITION | MF_POPUP | MF_STRING, (UINT)pSubMenu->m_hMenu, wfd.cFileName);
                    pSubMenu->Detach();
                    astrDirs.InsertAt(nPos, wfd.cFileName);
                    ++nLastDir;
                }
                delete pSubMenu;
            }
        } while(FindNextFile(h, &wfd));
        FindClose(h);
    }
    return nEndPos;
}


好了，菜单建立完了。万事大吉？没有。还要写命令处理函数。

afx_msg void OnMenu(UINT nID)

{

        ShellExecute(NULL,NULL,m_astrFavoriteURLs[nID-0xe00],NULL,NULL,SW_SHOWDEFAULT);

}

和消息映射

……

//}}AFX_MSG_MAP
ON_COMMAND_RANGE(0xe00, 0xfff, OnMenu)
END_MESSAGE_MAP()

这里我使用了0xe00到0xfff作为命令ID的范围，所以最多有512个文件菜单项（够用吗？不够用自己写一个数好了）。因为通常命令的ID大于327xx,所以不会和其他菜单冲突（倒是可能会和按钮ID冲突，自己注意一下资源ID范围就OK啦）。

好了，编译，运行，通过！

唯一的遗憾是没有文件的图标。由于我对操作系统不是很熟悉，不知道怎么才能得到文件的图标并画到菜单上面去。欢迎各方高人指教！

在Windows ME和Visual C++6 SP5下测试通过。

原文转自：http://www.ltesting.net