C++ ReadDirectoryChangesW 和 Boost 将目录更改作为文件（旧名称）返回

Question

我有一个应用程序正在监视目录的变化。但是，当我重命名目录时，假设将目录 A 更改为目录 B，我将看到以下输出结果：

File renamed (OLD): C:\A
Directory renamed (NEW): C:\B

虽然我期待输出：

Directory renamed (OLD): C:\A
Directory renamed (NEW): C:\B

这种情况也发生在删除目录时，给出输出：

File removed: C:\A\test.txt
File modified: C:\A
File removed: C:\A

虽然我期待输出：

File removed: C:\A\test.txt
Directory modified: C:\A
Directory removed: C:\A

我用来获得这个输出的代码（使用 Boost 的文件系统）是：

while(true) {
    FILE_NOTIFY_INFORMATION* info = reinterpret_cast<FILE_NOTIFY_INFORMATION*>(p);
    int ret = ::WideCharToMultiByte(CP_ACP, 0, info->FileName, info->FileNameLength / sizeof(WCHAR), FilePathChar, sizeof(FilePathChar), NULL, NULL);
    stringstream FilePathStream;
    FilePathStream << argv[1];
    FilePathStream << "\\";
    FilePathStream << FilePathChar;
    string FilePath = FilePathStream.str();
    cout << FilePath << endl;
    boost::filesystem::path path(FilePath);
    string Type = "File";
    if (boost::filesystem::is_directory(path)) {
        Type = "Directory";
        }
    ofstream myfile;
    myfile.open("changes.txt", std::ios_base::app);
    switch (info->Action) {
        case FILE_ACTION_ADDED:
            myfile << Type << " added: " << FilePath << "\n";
            break;
        case FILE_ACTION_MODIFIED:
            myfile << Type << " modified: " << FilePath << "\n";
            break;
        case FILE_ACTION_REMOVED:
            myfile << Type << " removed: " << FilePath << "\n";
            break;
        case FILE_ACTION_RENAMED_NEW_NAME:
            myfile << Type << " renamed (NEW): " << FilePath << "\n";
            break;
        case FILE_ACTION_RENAMED_OLD_NAME:
            myfile << Type << " renamed (OLD): " << FilePath << "\n";
            break;
        default:
            myfile << Type << " UNDISCOVERED ACTION: " << FilePath << "\n";
            break;
        }
    myfile.close();
    ::memset(FilePathChar, '\0', sizeof(FilePathChar));
    if (!info->NextEntryOffset) break;
    p += info->NextEntryOffset;
    }

我在这里做错了什么？

Answer 1

问题在于，在这两种情况下，您都不会收到通知，直到该目录不再被称为 C:\A（因为它已被删除或移动）。所以当你去的时候：

if (boost::filesystem::is_directory(path)) {
    Type = "Directory";
}

is_directory 返回false（所以你将Type 保留为"File"）

我建议改为：

const std::string Type = boost::filesystem::is_directory(path)    ? "Directory" :
                         boost::filesystem::is_regular_file(path) ? "File" :
                                                                    "unknown";