partial void Deletecustomer(customer instance);
partial void Insertcustomer(customer instance);
partial void Updatecustomer(customer instance);
private void btnFactuur_Click(object sender, RoutedEventArgs e) { if (cbKlant != null) { customer klant = (customer)cbKlant.SelectedItem; var begindatum = dtpBeginDatum.SelectedDate; var einddatum = dtpEindDatum.SelectedDate; List <order> orders = (from o in db.orders where o.customerId == klant.id && (o.date >= begindatum && o.date <= einddatum) select o).ToList(); foreach (order o in orders) { itemsinorder = (from itemsinorder in db.itemsinorders where o.id == itemsinorder.orderId select itemsinorder.productId).ToList(); int p = itemsinorder.Count(); var query = (from pricehistory in db.pricehistories join product in db.products on pricehistory.productId equals product.id join itemsinorder in db.itemsinorders on product.id equals itemsinorder.productId join order in db.orders on itemsinorder.id equals order.id where pricehistory.startdate <= order.date && (pricehistory.enddate >= order.date || pricehistory.enddate == null) && order.id == o.id select new { product.name, itemsinorder.amount, pricehistory.price }); foreach (var obj in query) { decimal totaal = obj.amount * obj.price; decimal totaalBestelling = +totaal; AlleProducten += ($"Order: {o.id} " + Environment.NewLine + "" + $"Datum: {o.date}" + Environment.NewLine + $"Product: {obj.name}" + Environment.NewLine + $"Aantal:{obj.amount}" + Environment.NewLine + $"Prijs per eenheid €{obj.price} " + Environment.NewLine + $"Totaal €{totaal}" + Environment.NewLine + $"Totaal bestelling €{totaalBestelling}" + Environment.NewLine); TotaalBedrag += totaal; } } MessageBox.Show($"+=+=+=+=+=+=+=+=+= Black Tulip Retail =+=+=+=+=+=+=+=+=+" + Environment.NewLine + Environment.NewLine + $"Naam: {klant.firstname} {klant.lastname}." + Environment.NewLine + $"Stad: {klant.city}" + Environment.NewLine + $"Telefoonnummer: {klant.phonenumber}" + Environment.NewLine + $"E-mailadres: {klant.email}" + Environment.NewLine + Environment.NewLine + $"Aantal bestellingen: {klant.orders.Count}" + Environment.NewLine + AlleProducten + Environment.NewLine + $"Totaal bedrag: €{TotaalBedrag}" + Environment.NewLine); } }