private void Button_Click_2(object sender, RoutedEventArgs e)
{
//we make sure there is at least one item in the cart and a sales person has been selected
if (ShoppingCart.Count > 0 && cbSalesPersonel.SelectedIndex > -1)
{
//auto dispose after no longer in scope
using (DBInvoiceSample db = new DBInvoiceSample())
{
//All database transactions are considered 1 unit of work
using (var dbTransaction = db.Database.BeginTransaction())
{
try
{
//we create the invoice object
Invoice inv = new Invoice();
inv.SaleDate = DateTime.Now;
//assign sales person by querying the database using the Combobox selection
inv.SalesPerson =
db.SalesPersons.SingleOrDefault(s => s.Id == (int) cbSalesPersonel.SelectedValue);
//for each product in the shopping cart we query the database
foreach (var prod in ShoppingCart)
{
//get product record with id
Product p = db.Products.SingleOrDefault(i => i.Id == prod.Id);
//reduce inventory
int RemainingItems = p.Qty - prod.Qty >= 0 ? (p.Qty - prod.Qty) : p.Qty;
if (p.Qty == RemainingItems)
{
MessageBox.Show(
string.Format(
"Unable to sell Product #{0} not enough inventory, Do want to continue?",
p.Id),
"Not Enough Inventory", MessageBoxButton.OK, MessageBoxImage.Asterisk);
//end transaction
dbTransaction.Rollback();
//exit procedure
return;
}
else
{
//If Qty is ok we sell the product
p.Qty = RemainingItems;
inv.SaleList.Add(p);
}
}
//we add the generated invoice to the Invoice Entity (Table)
db.Invoices.Add(inv);
//Save Changed to the database
db.SaveChanges();
//Make the changes permanent
dbTransaction.Commit();
//We restore the form with defaults
CleanUp();
//Show confirmation message to the user
MessageBox.Show(string.Format("Transaction #{0} Saved", inv.InvoiceId), "Success", MessageBoxButton.OK,
MessageBoxImage.Information);
}
catch
{
//if an error is produced, we rollback everything
dbTransaction.Rollback();
//We notify the user of the error
MessageBox.Show("Transaction Error, unable to generate invoice", "Fatal Error", MessageBoxButton.OK,
MessageBoxImage.Error);
}
}
}
}
else
{
MessageBox.Show("Please select at least one product and a Sales Person", "Data Error",
MessageBoxButton.OK, MessageBoxImage.Stop);
}
}
private void Window_Loaded(object sender, RoutedEventArgs e)
{
//Populates the combobox when the window loads
DBInvoiceSample db = new DBInvoiceSample();
cbSalesPersonel.ItemsSource = db.SalesPersons.ToList();
cbSalesPersonel.DisplayMemberPath = "Name";
cbSalesPersonel.SelectedValuePath = "Id";
cbSalesPersonel.SelectedIndex = 0;
}
private void Button_Click_1(object sender, RoutedEventArgs e)
{
//If a product code is not empty we search the database
if (Regex.IsMatch(TxtProdCode.Text.Trim(), @"^\d+$"))
{
DBInvoiceSample db = new DBInvoiceSample();
//parse the product code as int from the TextBox
int id = int.Parse(TxtProdCode.Text);
//We query the database for the product
Product p = db.Products.SingleOrDefault(x => x.Id == id);
if (p != null) //if product was found
{
//store in a temp variable (if user clicks on add we will need this for the Array)
tmpProduct = p;
//We display the product information on a label
cprod.Content = string.Format("ID: {0}, Name: {1}, Price: {2}, InStock (Qty): {3}", p.Id, p.Name, p.Price, p.Qty);
}
else
{
//if product was not found we display a user notification window
MessageBox.Show("Product not found. (Only numbers allowed)", "Product code error", MessageBoxButton.OK, MessageBoxImage.Exclamation);
}
}
}
