C#嵌套类

namespace ConsoleApplication11Anonymous
{
    class Class1
    {
        private int x;
        protected string str;
        static int y;


        public class Nested
        {
            int xx;
            string ss;
            void print()
            {
                //int y = x;  //error,不能访问外部的非静态成员
                int z = y;    //OK ,可以访问外部的静态成员
            }


            public Nested(Class1 A)
            {
                xx = A.x;   //通过外部类的实例来访问外部类私有成员
                ss = A.str; //通过外部类的实例来访问外部类保护成员
            }
        }
    }


    class Program
    {
        static void Main(string[] args)
        {
           
            Class1 X = new Class1();
            Class1.Nested CN = new Class1.Nested( X );
            
        }
    }
}

class Class2
    {
        private int x;
        static private int y;

        public void func()
        {
            //x = xx;   //当前上下文中不存在名称“xx”
            //x = zz;   //当前上下文中不存在名称“zz”
            //x = aa;   //当前上下文中不存在名称“aa”
            x = Nested.aa;
            Console.WriteLine(x);
        }

        public void funcs()
        {
            //这个只能访问Nested类的public成员
            Nested XX = new Nested();
            x = XX.zz;
            Console.WriteLine(x);
            //x = XX.aa;//访问静态成员只能通过类名而不是实例
            x = Nested.aa;
            Console.WriteLine(x);
        }

        private class Nested
        {
            private int xx;
            protected int yy;
            public int zz;
            public static int aa;
            
        }
    }