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

namespace ConsoleApplication1
{
    class Program
    {
        static void Main(string[] args)
        {
            // 裝箱
            int i = 3;
            object io = i;
            Console.WriteLine(
 
"i:{0}，io:{1}", i, io.ToString());
            // 拆箱
            int j = (int)io;
            Console.WriteLine("這是j=" + j);
        }
    }
}

具體可看：https://www.cnblogs.com/dabiaoge/p/4112581.html

這裡不抄錄