public void DoWork()
{
//客人訂了一份土司，不需要配料，列出他的價格與描述
IBreakfast bf1 = new Toast();
Console.WriteLine("餐點：{0} 價格：{1}", bf1.GetDescription(), bf1.GetCost());
//客人訂了一份貝果，要加"雙倍"火腿，列出他的價格與描述
IBreakfast bf2 = new Bego();
bf2 = new Ham(bf2);
bf2 = new Ham(bf2);
Console.WriteLine("餐點：{0} 價格：{1}", bf2.GetDescription(), bf2.GetCost());
//客人訂了一份漢堡，要加牛肉 生菜 起司，列出他的價格與描述
IBreakfast bf3 = new Hamburger();
bf3 = new Beef(bf3);
bf3 = new Lettuce(bf3);
bf3 = new Cheese(bf3);
Console.WriteLine("餐點：{0} 價格：{1}", bf3.GetDescription(), bf3.GetCost());
}