Question

I have an application where I can send emails. Now am asked to use ldap to authenticate the user email. Am very new to this concept. I have been given a ldap server link. No idea how to proceed with that. Any article or hits will be greatly helpful.

Here is the code am trying with

public static UserDetail GetUserDetails(string EmailId, string domainName)
{
    UserDetail userDetail = new UserDetail();

    try
    {
        string filter = string.Format("(&(ObjectClass={0})(sAMAccountName={1}))", "person", EmailId);
        string[] properties = new string[] { "fullname" };

        DirectoryEntry adRoot = new DirectoryEntry("LDAP://" + domainName, 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();
        string displayName = directoryEntry.Properties["displayName"[0].ToStrin();
        string firstName = directoryEntry.Properties["givenName"][0].ToString();
        string lastName = directoryEntry.Properties["sn"][0].ToString();
        string emailId = directoryEntry.Properties["mail"][0].ToString();

        userDetail.EmailId = emailId;
    }
    catch (Exception)
    {

    }
    return userDetail;
}

I want to achieve it on click of search button. How do I call the method and pass variables.

Answer 1

If you’re on .NET 3.5 or newer, you can use a PrincipalSearcher and a “query-by-example” principal to do your searching:

// create your domain context
PrincipalContext ctx = new PrincipalContext(ContextType.Domain);

// define a "query-by-example" principal - here, we search for a UserPrincipal 
// and with the e-mail of "[e-mail]"
UserPrincipal qbeUser = new UserPrincipal(ctx);
qbeUser.EmailAddress = "[e-mail]";

// create your principal searcher passing in the QBE principal    
PrincipalSearcher srch = new PrincipalSearcher(qbeUser);

// try to find that user
UserPrincipal found = srch.FindOne() as UserPrincipal;

if(found != null)
{
    // do whatever here - "found" is the user that matched the e-mail given
}
else
{
    // there wasn't any user with that e-mail address in your AD
}

If you haven’t already – absolutely read the MSDN article Managing Directory Security Principals in the .NET Framework 3.5 which shows nicely how to make the best use of the new features in System.DirectoryServices.AccountManagement. Or see the MSDN documentation on the System.DirectoryServices.AccountManagement namespace.

Of course, depending on your need, you might want to specify other properties on that “query-by-example” user principal you create:

• DisplayName (typically: first name + space + last name)
• SAM Account Name – your Windows/AD account name
• User Principal Name – your “[e-mail]” style name

You can specify any of the properties on the UserPrincipal and use those as “query-by-example” for your PrincipalSearcher.