using System;using System.Collections.Generic;using System.Linq;using System.Text;using System.Threading.Tasks;namespace Demo{    class MyClass    {        public int val; // 引用类型    }    struct myStruct    {        public int val;    }    class Program    {               static void Main(string[] args)        {            MyClass objectA = new MyClass();            MyClass objectB = objectA;            objectA.val = 10;            objectB.val = 20;            myStruct structA = new myStruct();            myStruct structB = structA;            structA.val = 30;            structB.val = 40;            Console.WriteLine("objectA.val = {0}",objectA.val);            Console.WriteLine("objectB.val = {0}", objectB.val);            Console.WriteLine("structA.val = {0}", structA.val);            Console.WriteLine("structB.val = {0}", structB.val);            Console.ReadKey();        }    }}

对象是引用类型，结构是值类型。

引用类型，操作同一个地址。

值类型，操作不同的地址。