Passing the servername/Ldap inside "DirectoryEntry" Vs "PrincipalContext" - asp.net

Question

I have this action method inside my ASP.NET MVC-5 .net 4.6:-
public ActionResult UsersInfo2()
{
List<DomainContext> results = new List<DomainContext>();
try
{
// create LDAP connection object
DirectoryEntry myLdapConnection = createDirectoryEntry();
string ADServerName = System.Web.Configuration.WebConfigurationManager.AppSettings["ADServerName"];
string ADusername = System.Web.Configuration.WebConfigurationManager.AppSettings["ADUserName"];
string ADpassword = System.Web.Configuration.WebConfigurationManager.AppSettings["ADPassword"];
using (var context = new DirectoryEntry("LDAP://mydomain.com:389/DC=mydomain,DC=com", ADusername, ADpassword))
using (var search = new DirectorySearcher(context))
{
SearchResult r = search.FindOne();
ResultPropertyCollection fields = r.Properties;
foreach (String ldapField in fields.PropertyNames)
string temp;
foreach (Object myCollection in fields[ldapField])
temp = String.Format("{0,-20} : {1}",
ldapField, myCollection.ToString());
}
}
using (var context = new PrincipalContext(ContextType.Domain, "mydomain.com", ADusername, ADpassword))
{
bool isvalid = context.ValidateCredentials("*******", "****************");
}
}
catch (Exception e)
{
Console.WriteLine("Exception caught:\n\n" + e.ToString());
}
return View(results);
}
so after around one day of testing i realize that for the DirectoryEntry I need to pass the server/ldap as follow ("LDAP://mydomain.com:389/DC=mydomain,DC=com", ADusername, ADpassword)) , while for the PrincipalContext we need to pass it as follow:- (ContextType.Domain, "mydomain.com", ADusername, ADpassword)).. so i can not pass the ldap inside the PrincipalContext nor the servrname only inside the DirectoryEntry .. so is this the case? or i am doing things wrongly ?
Thanks

Answer 1

You are correct.
The System.DirectoryServices.AccountManagement namespace (PrincipalContext, UserPrincipal, etc.) was created to simplify things. However, it just uses the System.DirectoryServices namespace (DirectoryEntry, etc.) in the background. (except for ValidateCredentials, which uses System.DirectoryServices.Protocols.LdapConnection).
I prefer to always use DirectoryEntry and friends because it gives me more control over performance. That's something I wrote an article about: Active Directory: Better performance