框架设计基本概念-第一篇

给大家介绍一个订单的设计，考虑到商品普通价和VIP打折后的不同订单金额

运行结果：

UML图：

Program.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ConsoleApplication50
{
    class Program
    {
        static void Main(string[] args)
        {

            IOperationPrice operationPrice = new OperationNormalPrice();

            Order order = new Order(operationPrice)
            {
                Status = OrderStatus.Active,
                Items = new Items()
            };
            Console.WriteLine("普通价：" + order.GetPrice());

            operationPrice = new OperationVipPrice();
            order = new Order(operationPrice)
            {
                Status = OrderStatus.Active,
                Items = new Items()
            };
            Console.WriteLine("*VIP价：" + order.GetPrice());

            Console.ReadKey();

        }
    }
}

Item.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ConsoleApplication50
{
    public class Item
    {
        public string ItemName { get; set; }
        public string ItemCode { get; set; }
        public int Price { get; set; }
    }
}

Items.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ConsoleApplication50
{
    public class Items : List<Item>, IEnumerable<Item>
    {
        public Items()
        {
            this.Add(new Item { ItemName = ".net高级编程", ItemCode = "001", Price = 100 });
            this.Add(new Item { ItemName = "程序员修炼", ItemCode = "002", Price = 200 });
        }
    }
}

IOperationPrice.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ConsoleApplication50
{
    public interface IOperationPrice
    {

        double GetPrice(Order order);

    }
}

OperationNormalPrice.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ConsoleApplication50
{
    public class OperationNormalPrice : IOperationPrice
    {
        public double GetPrice(Order order)
        {
            double result = 0;
            foreach (var item in order.Items)
            {
                result += item.Price;
            }
            return result;
        }
    }
}

OperationVipPrice.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ConsoleApplication50
{
    public class OperationVipPrice : IOperationPrice
    {
        public double GetPrice(Order order)
        {
            double result = 0;
            foreach (var item in order.Items)
            {
                result += item.Price-20;
            }
            return result;
        }
    }
}

Order.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ConsoleApplication50
{
    public class Order
    {

        public OrderStatus Status;
        public Items Items;

        private IOperationPrice OperationPrice;

        public Order(IOperationPrice operationPrice)
        {
            this.OperationPrice = operationPrice;
        }

        public double GetPrice()
        {
            return OperationPrice.GetPrice(this);
        }
    }

    public enum OrderStatus
    {
        Active = 1,
        DeActive = 2

    }
}