using System;

 namespace Test

 {

     class MainClass

     {

         //懒人写法的单例

         class Weapon

         {

             public static readonly Weapon Instance;

             static Weapon()

             {

                 Instance=new Weapon();

             }

         }

         class MyWeapon

         {

             //static readonly和const的区别

             public const int Speed=;//const必须赋值，且只能用这种方法赋值

             //static readonly 可以赋值也可以不赋值，也可以在用static修饰的构造方法中赋值

             public static readonly int Speed_1;

             public static readonly int Speed_2=;

             public static readonly int Speed_3;

             static MyWeapon()

             {

                 Speed_3=;

             }

         }

         public static void Main (string[] args)

         {

             //static readonly和const的联系，

             //在外边只能通过类名.访问，且在外部不能赋值（二者都是只读的）

             Console.WriteLine (MyWeapon.Speed_3);//

         }

     }

 }