public int GetIdempotentKey() { unchecked { int hashCode = CaptureNumber?.GetHashCode() ?? 0; hashCode = (hashCode * 397) ^ (CreditNoteNumber?.GetHashCode() ?? 0); hashCode = (hashCode * 397) ^ OrderItems.GetIdempotentListKey(); hashCode = (hashCode * 397) ^ (OrderNumber?.GetHashCode() ?? 0); return(hashCode); } }