How do I find a user's Active Directory display name in a C# web application?

Question

I'm writing a web application which uses windows authentication and I can happily get the user's login name using something like:

 string login = User.Identity.Name.ToString();

But I don't need their login name I want their DisplayName. I've been banging my head for a couple hours now...

Can I access my organisation's AD via a web application?

Answer 1

See related question: Active Directory: Retrieve User information

See also: Howto: (Almost) Everything In Active Directory via C# and more specifically section "Enumerate an object's properties".

If you have a path to connect to a group in a domain, the following snippet may be helpful:

GetUserProperty("<myaccount>", "DisplayName");

public static string GetUserProperty(string accountName, string propertyName)
{
 DirectoryEntry entry = new DirectoryEntry();
 // "LDAP://CN=<group name>, CN =<Users>, DC=<domain component>, DC=<domain component>,..."
 entry.Path = "LDAP://...";
 entry.AuthenticationType = AuthenticationTypes.Secure;

 DirectorySearcher search = new DirectorySearcher(entry);
 search.Filter = "(SAMAccountName=" + accountName + ")";
 search.PropertiesToLoad.Add(propertyName);

 SearchResultCollection results = search.FindAll();
 if (results != null && results.Count > 0)
 {
  return results[0].Properties[propertyName][0].ToString();
 }
 else
 {
         return "Unknown User";
 }
}

Answer 2

How about this:

private static string GetFullName()
    {
        try
        {
            DirectoryEntry de = new DirectoryEntry("WinNT://" + Environment.UserDomainName + "/" + Environment.UserName);
            return de.Properties["fullName"].Value.ToString();
        }
        catch { return null; }
    }

Answer 3

There is a CodePlex project for Linq to AD, if you're interested.

It's also covered in the book LINQ Unleashed for C# by Paul Kimmel - he uses the above project as his starting point.

not affiliated with either source - I just read the book recently

Answer 4

In case anyone cares I managed to crack this one:

      /// This is some imaginary code to show you how to use it

      Session["USER"] = User.Identity.Name.ToString();
      Session["LOGIN"] = RemoveDomainPrefix(User.Identity.Name.ToString()); // not a real function :D
      string ldappath = "LDAP://your_ldap_path";
      // "LDAP://CN=<group name>, CN =<Users>, DC=<domain component>, DC=<domain component>,..."


      Session["cn"] = GetAttribute(ldappath, (string)Session["LOGIN"], "cn");
      Session["displayName"] = GetAttribute(ldappath, (string)Session["LOGIN"], "displayName");
      Session["mail"] = GetAttribute(ldappath, (string)Session["LOGIN"], "mail");
      Session["givenName"] = GetAttribute(ldappath, (string)Session["LOGIN"], "givenName");
      Session["sn"] = GetAttribute(ldappath, (string)Session["LOGIN"], "sn");


/// working code

public static string GetAttribute(string ldappath, string sAMAccountName, string attribute)
    {
        string OUT = string.Empty;

        try
        {
            DirectoryEntry de = new DirectoryEntry(ldappath);
            DirectorySearcher ds = new DirectorySearcher(de);
            ds.Filter = "(&(objectClass=user)(objectCategory=person)(sAMAccountName=" + sAMAccountName + "))";

            SearchResultCollection results = ds.FindAll();

            foreach (SearchResult result in results)
            {
                OUT =  GetProperty(result, attribute);
            }
        }
        catch (Exception t)
        {
            // System.Diagnostics.Debug.WriteLine(t.Message);
        }

        return (OUT != null) ? OUT : string.Empty;
    }

public static string GetProperty(SearchResult searchResult, string PropertyName)
    {
        if (searchResult.Properties.Contains(PropertyName))
        {
            return searchResult.Properties[PropertyName][0].ToString();
        }
        else
        {
            return string.Empty;
        }
    }

Answer 5

FYI, there's a typo in the above code...

    SearchResultCollection results = ds.FindAll();
    foreach (SearchResult result in ds.FindAll())
    {
        OUT =  GetProperty(result, attribute);
    }

should read:

    SearchResultCollection results = ds.FindAll();
    foreach (SearchResult result in **results**)
    {
        OUT =  GetProperty(result, attribute);
    }

Hope that helps :-)