public static ModelStore LoadFrom(TextReader reader)
{
var store = new ModelStore();
try {
if (reader.ReadLine() != "DATA-BEGIN")
{
return(null);
}
while (true)
{
string line = reader.ReadLine();
if (line == null)
{
return(null);
}
else if (line == "DATA-END")
{
break;
}
string[] tokens = line.Split(';');
switch (tokens[0])
{
case "BOOK":
Book book = new Book
{
Id = int.Parse(tokens[1]), Title = tokens[2], Author = tokens[3],
Price = decimal.Parse(tokens[4])
};
if (book.Id < 0 || book.Price < 0 || tokens.Length != 5)
{
return(null);
}
store.books.Add(book);
break;
case "CUSTOMER":
Customer cust = new Customer
{
Id = int.Parse(tokens[1]), FirstName = tokens[2], LastName = tokens[3]
};
if (cust.Id < 0 || tokens.Length != 4)
{
return(null);
}
store.customers.Add(cust);
break;
case "CART-ITEM":
var customer = store.GetCustomer(int.Parse(tokens[1]));
if (customer == null)
{
return(null);
}
ShoppingCartItem item = new ShoppingCartItem
{
BookId = int.Parse(tokens[2]), Count = int.Parse(tokens[3])
};
if (store.GetBook(item.BookId) == null || item.Count < 0)
{
return(null);
}
customer.ShoppingCart.Items.Add(item);
break;
default:
return(null);
}
}
} catch (Exception ex) {
if (ex is FormatException || ex is IndexOutOfRangeException)
{
return(null);
}
throw;
}
return(store);
}
public void RemoveItem(ShoppingCartItem item)
{
Items.Remove(item);
}
