C#(委託a)

C#( a)
    public delegate double TheOperator(double x, double y);    
        
    public class Operators    
    {    
    　static public double Add(double x, double y)    
    　{    
    　　return x + y;    
    　}    
        
    　static public double Sub(double x, double y)    
    　{    
    　　return x - y;    
    　}    
        
    　// ，       
    }    
        
    public class DotNet_Calculator    
    {    
    　public double Foo(TheOperator op, double x, double y)    
    　{    
    　　return op(x, y);    
    　}    
    }    
        
    public class TheMainClass    
    {    
    　static public void Main()    
    　{    
    　　TheOperator myAdd = new TheOperator(Operators.Add);    
    　　TheOperator mySub = new TheOperator(Operators.Sub);    
        
    　　DotNet_Calculator dc = new DotNet_Calculator();    
    　　double sum = dc.Foo(myAdd, 2, 4); //sum = 6    
    　　System.Console.WriteLine(sum);    
    　　double sub = dc.Foo(mySub, 3, 7); //sub = -4    
    　　System.Console.WriteLine(sub);    
    　}    
    }    



C#( b)
// 
    public class MrZhang
    {
        // 
        public static void BuyTicket()
        {
            Console.WriteLine("NND, ， ！");
        }
    }

    // 
    class MrMing
    {
        // ， “ ”
        public delegate void BugTicketEventHandler();

        public static void Main(string[] args)
        {
            // ， MrZhang.BuyTicket“ ”
            BugTicketEventHandler myDelegate = new BugTicketEventHandler(MrZhang.BuyTicket);

            // 
            myDelegate();
            Console.ReadKey();
        }
    }