private:
CString m_strSearchPath;//搜索路径
private:
//获取子目录结构
void GetSubDirectories(LPNMTREEVIEW pNMTreeView);

const wchar_t PATH_SPACER[] = L"\\";//路径分隔符
///////////////////////////////////////////////////////////////////
//函数名称：GetSubDirectories
//函数介绍：
//   获取子目录结构
//输入参数：
//   pNMTreeView:一个用于传递消息的内容的结构体指针，
//   传递了TVN_SELCHANGED携带的消息内容
//输出参数：
//   无
//返回值：
//   无
///////////////////////////////////////////////////////////////////
void CFilesAssistantDlg::GetSubDirectories(LPNMTREEVIEW pNMTreeView)
{
//为没有打开的文件建立下级列表
HTREEITEM hTreeItem = pNMTreeView->itemNew.hItem;

//查找选定目录下的内容

//组合查询条件
wchar_t* strSearchPath = new wchar_t[MAX_PATH];
strSearchPath[0] = L'\0';

//组合完整路径，向上组合
wcscpy(strSearchPath, m_tcDirectories.GetItemText(hTreeItem));
wcscat(strSearchPath, PATH_SPACER);
HTREEITEM hTreeItemTemp = m_tcDirectories.GetParentItem(hTreeItem);
wchar_t* strTemp = new wchar_t[MAX_PATH];
while(NULL!=hTreeItemTemp)
{
wcscpy(strTemp, m_tcDirectories.GetItemText(hTreeItemTemp));
wcscat(strTemp, PATH_SPACER);
wcscat(strTemp, strSearchPath);
wcscpy(strSearchPath, strTemp);
hTreeItemTemp = m_tcDirectories.GetParentItem(hTreeItemTemp);
}

m_strSearchPath = strSearchPath;//复制到成员变量，用于文件列表
m_strSearchPath.Replace(L"\\\\", L"\\");
//增加过滤条件，由于是选择目录因此使用"*.*"
wchar_t strFileName[] = L"*.*";//选择所有的文件
wcscat(strSearchPath, strFileName);

//判定是否存在子项
BOOL bItemHasChildren = m_tcDirectories.ItemHasChildren(hTreeItem);
if (bItemHasChildren)
{
return;
}
//开始查找
WIN32_FIND_DATA FindData;//用于存储找到的文件
HANDLE hFind;//存储用于查找的句柄

hFind = FindFirstFile(strSearchPath, &FindData);

delete[] strSearchPath;
if (INVALID_HANDLE_VALUE == hFind)
{
return ;
}

//存在目录
m_lcFiles.DeleteAllItems();//清空文件列表
do
{
//添加目录
if (FILE_ATTRIBUTE_DIRECTORY == (FindData.dwFileAttributes&     FILE_ATTRIBUTE_DIRECTORY))
{
//不添加"."和".."
if ((0==wcscmp(L".", FindData.cFileName)) ||
(0==wcscmp(L"..", FindData.cFileName)))
{
continue;
}

//添加目录
m_tcDirectories.InsertItem(FindData.cFileName, hTreeItem);
}
}while( FindNextFile(hFind, &FindData));
FindClose(hFind);

m_tcDirectories.Expand(hTreeItem, TVE_EXPAND);
m_tcDirectories.SortChildren(hTreeItem);
}

void CFilesAssistantDlg::OnTvnSelchanged
TreeDirectories(NMHDR *pNMHDR,  LRESULT *pResult)
{
LPNMTREEVIEW pNMTreeView = reinterpret_cast<LPNMTREEVIEW>(pNMHDR);
*pResult = 0;
//获取目录结构
GetSubDirectories(pNMTreeView);
}

FilesAssistantDlg.h