using System;using System.Collections.Generic;using System.Linq;using System.Text;namespace ConsoleApplication1{    class C1    {        public readonly  int myvalue=http://www.mamicode.com/1;        public readonly static  int  value = http://www.mamicode.com/2;        public C1()        { myvalue = 3;             //value = http://www.mamicode.com/4;//无法对静态只读字段赋值(静态构造函数或变量初始值中除外)        }        static  C1()        {            //myvalue = http://www.mamicode.com/3;//非静态的字段、方法或属性“ConsoleApplication1.C1.myvalue”要求对象引用            value = 4;        }    }    class Program    {        static void Main(string[] args)        {            C1 C = new C1();            Console.WriteLine("myvalue:{0}", C.myvalue);            //C.myvalue = http://www.mamicode.com/20;//无法对只读的字段赋值(构造函数或变量初始值指定项中除外)            //C1.value = http://www.mamicode.com/20;//无法对只读的字段赋值(构造函数或变量初始值指定项中除外)            Console.WriteLine("value:{0}", C1.value);            Console.ReadLine();        }    }}//const字段只能在编译的时候决定，也就是说只能在字段声明的语句中初始化。而readonly字段可以在静态构造函数中完成的！
//readonly字段的值只能在字段的声明语句中和类的任何构造函数中设置