You can access the department by checking its underlying properties in its DirectoryEntry
var property = "department";
var directoryEntry = p.GetUnderlyingObject() as DirectoryEntry;
if (directoryEntry.Properties.Contains(property)) {
dc.Department = directoryEntry.Properties[property].Value.ToString();
}
You could consider converting the above into an extension method to reduce the repeated code.
I compiled a list of user properties into a class as constants
public static class ADUserProperties
{
public const String OBJECTCLASS = "objectClass";
public const String CONTAINERNAME = "cn";
public const String LASTNAME = "sn";
public const String COUNTRYNOTATION = "c";
public const String CITY = "l";
public const String STATE = "st";
public const String TITLE = "title";
public const String POSTALCODE = "postalCode";
public const String PHYSICALDELIVERYOFFICENAME = "physicalDeliveryOfficeName";
public const String FIRSTNAME = "givenName";
public const String MIDDLENAME = "initials";
public const String DISTINGUISHEDNAME = "distinguishedName";
public const String INSTANCETYPE = "instanceType";
public const String WHENCREATED = "whenCreated";
public const String WHENCHANGED = "whenChanged";
public const String DISPLAYNAME = "displayName";
public const String USNCREATED = "uSNCreated";
public const String MEMBEROF = "memberOf";
public const String USNCHANGED = "uSNChanged";
public const String COUNTRY = "co";
public const String DEPARTMENT = "department";
public const String COMPANY = "company";
public const String PROXYADDRESSES = "proxyAddresses";
public const String STREETADDRESS = "streetAddress";
public const String DIRECTREPORTS = "directReports";
public const String NAME = "name";
public const String OBJECTGUID = "objectGUID";
public const String USERACCOUNTCONTROL = "userAccountControl";
public const String BADPWDCOUNT = "badPwdCount";
public const String CODEPAGE = "codePage";
public const String COUNTRYCODE = "countryCode";
public const String BADPASSWORDTIME = "badPasswordTime";
public const String LASTLOGOFF = "lastLogoff";
public const String LASTLOGON = "lastLogon";
public const String PWDLASTSET = "pwdLastSet";
public const String PRIMARYGROUPID = "primaryGroupID";
public const String OBJECTSID = "objectSid";
public const String ADMINCOUNT = "adminCount";
public const String ACCOUNTEXPIRES = "accountExpires";
public const String LOGONCOUNT = "logonCount";
public const String LOGINNAME = "sAMAccountName";
public const String SAMACCOUNTTYPE = "sAMAccountType";
public const String SHOWINADDRESSBOOK = "showInAddressBook";
public const String LEGACYEXCHANGEDN = "legacyExchangeDN";
public const String USERPRINCIPALNAME = "userPrincipalName";
public const String EXTENSION = "ipPhone";
public const String SERVICEPRINCIPALNAME = "servicePrincipalName";
public const String OBJECTCATEGORY = "objectCategory";
public const String DSCOREPROPAGATIONDATA = "dSCorePropagationData";
public const String LASTLOGONTIMESTAMP = "lastLogonTimestamp";
public const String EMAILADDRESS = "mail";
public const String MANAGER = "manager";
public const String MOBILE = "mobile";
public const String PAGER = "pager";
public const String FAX = "facsimileTelephoneNumber";
public const String HOMEPHONE = "homePhone";
public const String MSEXCHUSERACCOUNTCONTROL = "msExchUserAccountControl";
public const String MDBUSEDEFAULTS = "mDBUseDefaults";
public const String MSEXCHMAILBOXSECURITYDESCRIPTOR = "msExchMailboxSecurityDescriptor";
public const String HOMEMDB = "homeMDB";
public const String MSEXCHPOLICIESINCLUDED = "msExchPoliciesIncluded";
public const String HOMEMTA = "homeMTA";
public const String MSEXCHRECIPIENTTYPEDETAILS = "msExchRecipientTypeDetails";
public const String MAILNICKNAME = "mailNickname";
public const String MSEXCHHOMESERVERNAME = "msExchHomeServerName";
public const String MSEXCHVERSION = "msExchVersion";
public const String MSEXCHRECIPIENTDISPLAYTYPE = "msExchRecipientDisplayType";
public const String MSEXCHMAILBOXGUID = "msExchMailboxGuid";
public const String NTSECURITYDESCRIPTOR = "nTSecurityDescriptor";
}
and created an extension method to access it
public static string GetProperty(this DirectoryEntry directoryEntry , string propertyName, int index = 0) {
if (directoryEntry.Properties.Contains(propertyName) && index > -1 && index < directoryEntry.Properties[propertyName].Count) {
return directoryEntry.Properties[propertyName][index].ToString();
} else {
return string.Empty;
}
}
public static string GetProperty(this Principal principal, string property) {
var directoryEntry = principal.GetUnderlyingObject() as DirectoryEntry;
return directoryEntry.GetProperty(property);
}
This would then allow your code to be updated to
dc.Department = p.GetProperty(ADUserProperties.DEPARTMENT);