read email from active directory

 private static string GetEmailAddressLDAP(string strEnv, string empno)

    {

      string strLDAPConnection;

      string strLDAPId;

      string strLDAPPwd;

      if (strEnv.IndexOf("P") == 0)

      {

        //'PROD

        strLDAPConnection = "LDAP://xxxx/ou=xxxx,dc=xx,dc=xxx";

        strLDAPId = @"xxxxxxxxxx";

        strLDAPPwd = "xxxxxxx";

      }

      DirectoryEntry entry = new DirectoryEntry(strLDAPConnection, strLDAPId, strLDAPPwd);

      DirectorySearcher search = new DirectorySearcher(entry);

      char pad = '0';

      search.Filter = String.Format("(sAMAccountName=*{0})", empno.PadLeft(6, pad).Substring(empno.PadLeft(6, pad).Length - 6));

      SearchResult result = search.FindOne();

      if (result != null)

      {

        DirectoryEntry currentUser = result.GetDirectoryEntry();

        if (currentUser.Properties["mail"].Value != null)

        {

          string sEmail = currentUser.Properties["mail"].Value.ToString();

          return sEmail;

        }

        else

        {

          return "email not found";

        }

      }

      else

      {

        return "employee NOT FOUND";

      }

    }