/// <summary>
 /// ReIndexes an Invoice
 /// </summary>
 /// <param name="invoice">The <see cref="IInvoice"/> to be re-indexed</param>
 private static void IndexInvoice(IInvoice invoice)
 {
     if (invoice != null && invoice.HasIdentity)
     {
         InvoiceIndexer.AddInvoiceToIndex(invoice);
     }
 }
 /// <summary>
 /// Deletes an <see cref="IInvoice"/> from the index
 /// </summary>
 /// <param name="invoice">The <see cref="IInvoice"/> to be removed from the index</param>
 private static void DeleteInvoiceFromIndex(IInvoice invoice)
 {
     InvoiceIndexer.DeleteFromIndex(((Invoice)invoice).ExamineId.ToString(CultureInfo.InvariantCulture));
 }