public async Task <bool> StoreInvoice(Invoice invoice)
{
if (invoice.InvoiceNumber <= 0)
{
throw new InvalidInvoiceNumberException();
}
var beforeSavingEventArgs = new InvoiceBeforeSavingEventArgs();
OnBeforeSaving(beforeSavingEventArgs);
if (beforeSavingEventArgs.Cancel)
{
return(false);
}
// Process of saving to a remote database would be here...
await Task.Delay(500);
OnSaved(EventArgs.Empty);
return(true);
}
protected virtual void OnBeforeSaving(InvoiceBeforeSavingEventArgs e)
{
BeforeSaving?.Invoke(this, e);
}