How to get domain user information from Active Directory in C#
First, we have to know the user connection name (here from an ASP.NET page).
string principal = this.Context.User.Identity.Name;
Then we have to define some stuff :
- search filter including object type and connection name,
- domain,
- properties to retrieve from Active Directory.
string filter = string.Format("(&(ObjectClass={0})(sAMAccountName={1}))", "person", principal);
string domain = "DOMAIN";
string[] properties = new string[] { "fullname" };
To search in Active Directory, we need the following objects :
- DirectoryEntry : represents a node or object in the Active Directory hierarchy,
- DirectorySearcher : performs queries against Active Directory Domain Services.
DirectoryEntry adRoot = new DirectoryEntry("LDAP://" + domain, null, null, AuthenticationTypes.Secure);
DirectorySearcher searcher = new DirectorySearcher(adRoot);
searcher.SearchScope = SearchScope.Subtree;
searcher.ReferralChasing = ReferralChasingOption.All;
searcher.PropertiesToLoad.AddRange(properties);
searcher.Filter = filter;
SearchResult result = searcher.FindOne();
DirectoryEntry directoryEntry = result.GetDirectoryEntry();
Finally, once information is retrieved in the DirectoryEntry object, we can get the details of each property defined.
string displayName = directoryEntry.Properties["displayName"][0].ToString();
string firstName = directoryEntry.Properties["givenName"][0].ToString();
string lastName = directoryEntry.Properties["sn"][0].ToString();
string email = directoryEntry.Properties["mail"][0].ToString();