public static List <Order> FilterOrders(string?customerId, int?productId)
{
using (var db = new SouthwindContext())
{
var orders = RetrieveAllOrders();
var filteredCustomer = new List <Order>();
var filteredProducts = new List <Order>();
if (customerId == null)
{
filteredCustomer = orders;
}
else
{
foreach (var order in orders)
{
if (order.CustomerId == customerId)
{
filteredCustomer.Add(order);
continue;
}
}
}
if (productId == null)
{
filteredProducts = filteredCustomer;
}
else
{
foreach (var order in filteredCustomer)
{
if (DoesOrderHaveThisProduct(order, productId))
{
filteredProducts.Add(order);
continue;
}
}
}
return(filteredProducts);
}
}
public static void DeleteCustomer(string customerId)
{
using (var db = new SouthwindContext())
{
var ordersByThisCustomer =
from o in db.Orders
where o.CustomerId == customerId
select o.OrderId;
foreach (var o in ordersByThisCustomer)
{
DeleteOrder(o);
}
db.Customers.Remove(db.Customers.Find(customerId));
db.SaveChanges();
}
}
public static bool DoesOrderHaveThisProduct(Order order, int?productId)
{
using (var db = new SouthwindContext())
{
var orderDetailsForThisOrder =
db.Orders
.Include(o => o.OrderDetails)
.Where(o => o.OrderId == order.OrderId)
.Select(p => p.OrderDetails)
.FirstOrDefault();
foreach (var orderDetail in orderDetailsForThisOrder.ToList())
{
if (orderDetail.ProductId == productId)
{
return(true);
}
}
return(false);
}
}
public string GetReceipt(Order order)
{
using (var db = new SouthwindContext())
{
var orderList = db.OrderDetails.Include(o => o.Order).ThenInclude(c => c.Customer).Include(p => p.Product).Where(o => o.OrderId == order.OrderId).ToList();
var message = $"OrderID :{order.OrderId}\n{orderList[0].Order.Customer.ContactName}\nOrder made on: {order.OrderDate}";
var total = 0m;
if (orderList != null)
{
foreach (var item in orderList)
{
message += $"\n\t{item.Product.ProductName} - {item.UnitPrice.ToString("c")}";
total += item.UnitPrice;
}
message += $"\n -------------\n Total Price: {total.ToString("c")}";
return(message);
}
return("");
}
}
public CustomerService(SouthwindContext dbContext)
{
// 呼叫端有注入 DbContext 物件，就用對方提供的。
this.db = dbContext;
}
public CustomerService(SouthwindContext dbContext)
{
// 呼叫端有注入 DbContext 物件，就用對方提供的。
this.db = dbContext;
}
public CustomerService()
{
// 提供預設的 DbContext 物件。
db = SouthwindContext.InstanceInCurrentRequest;
}
public CustomerService()
{
// 提供預設的 DbContext 物件。
db = new SouthwindContext();
}
public CustomerService()
{
// 提供預設的 DbContext 物件。
db = SouthwindContext.InstanceInCurrentRequest;
}
public CustomerService()
{
// 提供預設的 DbContext 物件。
db = new SouthwindContext();
}
/// <summary>
/// 调用方注入DbContext对象
/// </summary>
public CustomerService(SouthwindContext dbContext)
{
this.db = dbContext;
}
public CustomerService()
{
// 提供默认的DbContext对象
db = new SouthwindContext();
}