C# 委托简单例子

public delegate double Delegate_Prod(int a,int b);
class Class1
{
    static double fn_Prodvalues(int val1,int val2)
    {
        return val1*val2;
    }
    static void Main(string[] args)
    {
        //Creating the Delegate Instance
        Delegate_Prod delObj = new Delegate_Prod(fn_Prodvalues);
        Console.Write("Please Enter Values");
        int v1 = Int32.Parse(Console.ReadLine());
        int v2 = Int32.Parse(Console.ReadLine());
        //use a delegate for processing
        double res = delObj(v1,v2);
        Console.WriteLine ("Result :"+res);
        Console.ReadLine();
    }
}

namespace ConsoleApplication
{
    //定义代理
    delegate String Mydelegate();
    class temp
    {
        static void Main(String[] args)
        {
            //实例化代理
            Mydelegate Md = new Mydelegate(AsyncMethod);
            //实例一个回调代理
            AsyncCallback callback = new AsyncCallback(callbackMethod);
            //开始执行异步方法
            Md.BeginInvoke(callback, Md);
            Console.ReadLine();
        }
        //异步调用的方法
        static String AsyncMethod()
        {
            Console.WriteLine("异步方法正执行");
            String str = "异步调用已结束";
            return str;
        }

        //回调方法
        static void callbackMethod(IAsyncResult Ias)
        {
            Mydelegate Md = (Mydelegate)Ias.AsyncState;
            String  str = Md.EndInvoke(Ias);
            Console.WriteLine(str);
        }
    }
}