in MvcMusicStore/Controllers/CheckoutController.cs [66:81]
public ActionResult Complete(int id)
{
// Validate customer owns this order
bool isValid = storeDB.Orders.Any(
o => o.OrderId == id &&
o.Username == User.Identity.Name);
if (isValid)
{
return View(id);
}
else
{
return View("Error");
}
}