CODEWITHSUNDEEP
c#existsdirectoryentry
John
John

Reputation: 103

if directoryEntry does not exist

Using Directory Entry in asp.net c#, if I call:

ADUtils newAdClass = new ADUtils("dl-dom", "ad.test", "Password?1");
    List<string> domUsers = newAdClass.GetDomainUsers();
----------------------------------------------------------------------------------
-------------------------------------------------------------------------------

public List<string> GetDomainUsers()
{
    //returned list
    List<string> domainUsers = new List<string>();

    //create connection
    DirectoryEntry entry = new DirectoryEntry(_lDAPPath, _ldapUser, _ldapPassword);
    DirectorySearcher search = new DirectorySearcher(entry);

    //search subtree nodes
    search.SearchScope = SearchScope.Subtree;

    //Active Directory LDAP: All email users (alternate)
    search.Filter = "(&(objectClass=user)(objectcategory=person))";

    //create results objects from search object 
    SearchResultCollection results = search.FindAll();

    //run through list, for each entry remove 'CN=' and add 'user' to list
    for (int i = 0; i < results.Count; i++)
    {
        DirectoryEntry de = results[i].GetDirectoryEntry();
        string user = de.Name.Replace("CN=", "");
        domainUsers.Add(user);
    }
    return domainUsers;
}

This works fine however upon testing if the user enters a domain that does not exist. e.g.

ADUtils newAdClass = new ADUtils("FAKE-dl-dom", "ad.test", "Password?1");

this throws an error inside my code so im attempting to use http://msdn.microsoft.com/en-us/library/system.directoryservices.directoryentry.exists%28v=vs.110%29.aspx exists

but DirectoryEntry entry returns an object where as I need to test the string, I think the path is wrong...any ideas? 

string entry1 = _lDAPPath + "," + _ldapUser + "," + _ldapPassword;
//entry1 returns: LDAP://DC=dl-dom,ad.test,Password?1

if (DirectoryEntry.Exists(entry1))
{
    DirectorySearcher search = new DirectorySearcher(entry);

when I use the above code I get the exception

An invalid dn syntax has been specified.

constructor:

public ADUtils(string LDAPDomain, string ADUser, string ADUserPwd)
{
    _lDAPPath = "LDAP://DC=" + LDAPDomain;
    _ldapUser = ADUser;
    _ldapPassword = ADUserPwd;
}

Upvotes: 0

Views: 2628

Answers (2)

baldpate
baldpate

Reputation: 1749

For example, assume domain is "example.com"
The path to test should be LDAP://example.com.

If you do not provide the DN, it will automatically connect to the domain root object. So in above example, the object it actually get is LDAP://example.com/DC=example,DC=com

Upvotes: 0

Joel Coehoorn
Joel Coehoorn

Reputation: 416121

Don't use the Exists() function to test before accessing. The LDAP directory is volatile, and can change out from under you. This is a race condition.

Instead, use a try/catch block, and handle the exception if it fails:

try
{
    //create results objects from search object 
    SearchResultCollection results = search.FindAll();

    //run through list, for each entry remove 'CN=' and add 'user' to list
    for (int i = 0; i < results.Count; i++)
    {
        DirectoryEntry de = results[i].GetDirectoryEntry();
        string user = de.Name.Replace("CN=", "");
        domainUsers.Add(user);
    }
}
catch(Excpetion e)
{
    //add code here to process the error

    //after debugging, you may even decide to just swallow the exception 
    // and return an empty collection
}

Upvotes: 0

Related Questions