注意事项

注意：①64位操作系统注册表会重定向，RegOpenKeyEx第4个参数得加上KEY_WOW64_64KEY；②RegOpenKeyEx遍历子项时注意第2和第4参数，参考图：

③RegQueryValueEx同样得注意第6参数

完整代码

std::unordered_map<std::string, std::string> GetAllAutoCADInstallPaths() 
{// 定义结果映射，键为版本号，值为安装路径std::unordered_map<std::string, std::string> installPaths;// 打开 AutoCAD 注册表项HKEY hKey;LONG lResult = RegOpenKeyEx(HKEY_LOCAL_MACHINE, "SOFTWARE\\Autodesk\\AutoCAD", 0, KEY_READ | KEY_WOW64_64KEY, &hKey);if (lResult != ERROR_SUCCESS) return installPaths;DWORD dwIndex = 0;TCHAR szSubKeyName[MAX_PATH];DWORD dwSize = sizeof(szSubKeyName);vector<string> vecSubKey;// 遍历子项while ((lResult = RegEnumKeyEx(hKey, dwIndex, szSubKeyName, &dwSize, NULL, NULL, NULL, NULL)) == ERROR_SUCCESS) {vecSubKey.emplace_back(string("SOFTWARE\\Autodesk\\AutoCAD\\")+szSubKeyName);++dwIndex;dwSize = MAX_PATH;}vector<string> vecSubSubKey;for (auto &strKey : vecSubKey){HKEY hSubKey;LONG lResult = RegOpenKeyEx(HKEY_LOCAL_MACHINE, strKey.c_str(), 0, KEY_READ | KEY_WOW64_64KEY, &hSubKey);if (lResult != ERROR_SUCCESS) return installPaths;dwIndex = 0;while ((lResult = RegEnumKeyEx(hSubKey, dwIndex, szSubKeyName, &dwSize, NULL, NULL, NULL, NULL)) == ERROR_SUCCESS) {vecSubSubKey.emplace_back(strKey + "\\" + szSubKeyName);++dwIndex;dwSize = MAX_PATH;}// 关闭键RegCloseKey(hSubKey);}for(auto &strKey : vecSubSubKey){HKEY hSubKey;LONG lResult = RegOpenKeyEx(HKEY_LOCAL_MACHINE, strKey.c_str(), 0, KEY_READ| KEY_WOW64_64KEY, &hSubKey);if (lResult != ERROR_SUCCESS) return installPaths;char installPath[MAX_PATH];char name[MAX_PATH];DWORD size = MAX_PATH;if(RegQueryValueEx(hSubKey, "Location", NULL, NULL, reinterpret_cast<LPBYTE>(installPath), &size) == ERROR_SUCCESS) {size = MAX_PATH;RegQueryValueEx(hSubKey, "ProductName", NULL, NULL, reinterpret_cast<LPBYTE>(name), &size);installPaths[string(name)] = string(installPath);;}// 关闭键RegCloseKey(hSubKey);}// 关闭键RegCloseKey(hKey);return installPaths;
}