public IHttpActionResult UpdateItems(int id, [FromBody] InvoiceModel invoice)
        {
            if (invoice == null ||
                invoice.DocEntry != id)
            {
                return(BadRequest());
            }

            try
            {
                var invFound = _invoices.UpdateItems(id, invoice);
                if (!invFound)
                {
                    return(NotFound());
                }

                return(Ok());
            }
            catch (Exception ex)
            {
                return(BadRequest(ex.Message));
            }
        }