How to get list of OU name in AD using DomainName using c#?

Question

i want to get list of OU from Active Directory.

i have only domain name.

how can i achieve this using c#?

Answer 1

Try something like this:

// connect to "RootDSE" to find default naming context
DirectoryEntry rootDSE = new DirectoryEntry("LDAP://RootDSE");

string defaultContext = rootDSE.Properties["defaultNamingContext"][0].ToString();

// bind to default naming context - if you *know* where you want to bind to - 
// you can just use that information right away
DirectoryEntry domainRoot = new DirectoryEntry("LDAP://" + defaultContext);

// set up directory searcher based on default naming context entry
DirectorySearcher ouSearcher = new DirectorySearcher(domainRoot);

// SearchScope: OneLevel = only immediate subordinates (top-level OUs); 
// subtree = all OU's in the whole domain (can take **LONG** time!)
ouSearcher.SearchScope = SearchScope.OneLevel;
// ouSearcher.SearchScope = SearchScope.Subtree;

// define properties to load - here I just get the "OU" attribute, the name of the OU
ouSearcher.PropertiesToLoad.Add("ou");

// define filter - only select organizational units
ouSearcher.Filter = "(objectCategory=organizationalUnit)";

// do search and iterate over results
foreach (SearchResult deResult in ouSearcher.FindAll())
{
    string ouName = deResult.Properties["ou"][0].ToString();
}

If you have a domain name (eg mycompany.com ), then the LDAP root domain typically will be called dc=mycompany,dc=com - that's a convention, it doesn't have to be that way though. That's why I'm connecting to the LDAP://RootDSE virtual LDAP root and I read out the property Default Naming Context which gives me the default LDAP path.

If you know where you want to connect to - feel free to skip that first step and just provide the valid LDAP path (eg LDAP://dc=YourCompany,dc=co,dc=jp or whatever) to create the domainRoot directory entry.

Answer 2

Add a reference to System.DirectoryServices in the project

    public static List<string> ListOu()
    {
        List<string> ous = new List<string>();
        using (DirectoryEntry root = new DirectoryEntry("LDAP://dc=DOMAIN,dc=COM"))
        {
            DirectorySearcher searcher = new DirectorySearcher(root);
            searcher.Filter = "(&(objectClass=organizationalUnit))";
            searcher.SearchScope = SearchScope.Subtree;
            searcher.PropertiesToLoad.Add("distinguishedName");

            var result = searcher.FindAll();
            foreach (SearchResult entry in result)
            {
                ous.Add(entry.GetDirectoryEntry().Properties["distinguishedName"].Value.ToString());
            }        

            result.Dispose();
            searcher.Dispose();
        }
        return ous;
    }