/*
A Programmer's Introduction to C# (Second Edition)
by Eric Gunnerson
Publisher: Apress L.P.
ISBN: 1-893115-62-3
*/
// 18 - Properties\Side Effects When Setting Values
// copyright 2000 Eric Gunnerson
using System;
using System.Collections;
class Basket
{
internal void UpdateTotal()
{
total = 0;
foreach (BasketItem item in items)
{
total += item.Total;
}
}
ArrayList items = new ArrayList();
Decimal total;
}
public class BasketItem
{
BasketItem(Basket basket)
{
this.basket = basket;
}
public int Quantity
{
get
{
return(quantity);
}
set
{
quantity = value;
basket.UpdateTotal();
}
}
public Decimal Price
{
get
{
return(price);
}
set
{
price = value;
basket.UpdateTotal();
}
}
public Decimal Total
{
get
{
// volume discount; 10% if 10 or more are purchased
if (quantity >= 10)
return(quantity * price * 0.90m);
else
return(quantity * price);
}
}
int quantity; // count of the item
Decimal price; // price of the item
Basket basket; // reference back to the basket
}
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