C#

public static bool IsAdministrator(this WindowsIdentity identity)
{
    if (identity == null) throw new ArgumentNullException(nameof(identity));
    
    WindowsPrincipal principal = new WindowsPrincipal(identity);
    if (principal.IsInRole(WindowsBuiltInRole.Administrator)) return true; // Elevated
    
    return identity.FindAll(ClaimTypes.DenyOnlySid).Any(c => c.Value == "S-1-5-114");
}

Security identifiers (Windows 10) | Microsoft Docs[^]:

S-1-5-114
Local account and member of Administrators group
You can use this SID when restricting network logon to local accounts instead of "administrator" or equivalent. This SID can be effective in blocking network logon for local users and groups by account type regardless of what they are actually named.

public interface IExtraProperty
{
     // Something like this
     public int ExtraPoperty { get;  set; }
}

public class MyClass : IExtraProperty

public static string ToXml(Soap.EventCode.EvCodes value)
      {
          string returnValue = null; // provide your default value
          switch (value)
          {
              case Soap.EventCode.EvCodes.DispatchedForDelivery:
              case Soap.EventCode.EvCodes.Delivered:
                  returnValue ="OD"; break;
              case Soap.EventCode.EvCodes.DepartedFromTerminal:
                  returnValue ="L1"; break;
          }
          return returnValue;
      }

public class EventCode
   {
       public static string ToXml(Soap.EventCode.EvCodes value)
       {
           switch (value)
           {
               case Soap.EventCode.EvCodes.DispatchedForDelivery:
               case Soap.EventCode.EvCodes.Delivered:
                   return "OD";
               case Soap.EventCode.EvCodes.DepartedFromTerminal:
                   return "L1";
               // Catch-all for all other cases. 
               // Throwing an exception here is just an example implementation, not mandatory.
               default: throw new ArgumentOutOfRangeException(nameof(value), "Unsupported Evcode: " + value);

           }
       }
   }