class program   
    {
        static void Main(string[] args)
        {
            Commodities[] c = new Commodities[3];
            
            for (int i = 0; i < 3; i++)
            {
                Console.WriteLine("添加第{0}件商品:\n请输入商品编号:",i+1);
                c[i]=new Commodities();
                c[i].id = int.Parse(Console.ReadLine());
                Console.WriteLine("请输入商品名:");
                c[i].name = Console.ReadLine();
                Console.WriteLine("请输入单价:");
                c[i].price = Convert.ToDouble(Console.ReadLine());
                Console.WriteLine("添加成功.");
            }
        }
    }
    class Commodities
    {
        public int id;
        public string name;
        public double price;
    }比如说这样
所有商品如下:
编号 商品名 价格
1   玉米    3.0
2