using System;
using System.Collections.Generic;
using System.Linq;

namespace blogs
{
    class Program
    {
        static void Main(string[] args)
        {
            var orderItems = new List<OrderItem>() {
                new OrderItem(){
                    GoodsName="鸭(包杀)",
                    Quantity=1
                },
                new OrderItem(){
                    GoodsName="鸭(不包杀)",
                     Quantity=1
               },
                new OrderItem(){
                    GoodsName="苹果",
                    Quantity=1

                },
                new OrderItem(){
                    GoodsName="鸭(包杀)",
                    Quantity=1
                }
            };

            var result = orderItems.GroupBy(m => m.GoodsName).Select(m => new
            {
                GoodsName = m.Key,
                Quantity = m.Count()
            }).OrderByDescending(m => m.Quantity);

            foreach (var item in result)
            {
                Console.WriteLine($"商品名: {item.GoodsName} 份数: {item.Quantity}");
            }
        }
    }
    class OrderItem
    {
        // 商品名,
        public string GoodsName { get; set; }


        //份数

        public int Quantity { get; set; }
    }


}