C#的委托

using System;
using System.IO;

namespace ConsoleApplication2
{
    delegate int NumberChanger(int n);
    class Program
    {
        static int num = 10;
       
        static void Main(string[] args)
        {
            NumberChanger nc1 = new NumberChanger (AddNum);
            nc1(25);
            Console.WriteLine("Value of Number:{0}",num);
            MyClass mc = new MyClass();
            NumberChanger nc2 = new NumberChanger(mc.AddNum);
            nc2(35);
            Console.WriteLine("Value of instance:{0}",mc.num);
            NumberChanger nc3 = new NumberChanger(mc.MutliNum);
            nc3(2);
            Console.WriteLine("Value of instance:{0}", mc.num);
            Console.ReadLine();
        }
        public static int AddNum(int p)
        {
            num += p;
            return num;
        }
     
    }
    class MyClass
    {
       public  int num = 10;
        public int AddNum(int p)
        {
            num += p;
            return num;
        }
        public int MutliNum(int p)
        {
            num *= p;
            return num;
        }
    }
   
}