https://docs.microsoft.com/zh-cn/windows/win32/adsi/search-filter-syntax?redirectedfrom=MSDN
https://blog.csdn.net/bytxl/article/details/11556195
// Create a new DirectorySearcher that starts at the root. // You can start it anywhere you want though // by providing a value in the DirectoryEntry constructor. DirectorySearcher searcher = new DirectorySearcher(new DirectoryEntry()); // Set the scope to Subtree in order to search all children. searcher.SearchScope = SearchScope.Subtree; // Set the filter to only look for Organizational Units// that have the name you are looking for. searcher.Filter = "(&(objectClass=organizationalUnit)(name=" + ouName + "))"; // If you are looking for only one result then do the following two things.SearchResult results = searcher.FindOne(); this.Properties = results.GetDirectoryEntry();