C#实践——委托实例应用

 要求：委托对象的应用，利用委托创建对象，运用加、减运算，运用GetInvocationList 方法。

 实践：

using System;
using System.Collections.Generic;
using System.Text;namespace Lab3
{
    delegate void myDelegate(double param1, double param2);
    class DelegateTest
    {
        public void myAdd(double param1, double param2)
        {
            double result = param1 + param2;
            Console.WriteLine(" I am using Add() !" );
            Console.WriteLine("  {0}+{1}={2}",param1,param2,result);
        }
        public void mySub(double param1, double param2)
        {
            double result = param1 - param2;
            Console.WriteLine(" I am user Sub() !");
            Console.WriteLine("  {0}-{1}={2}", param1, param2, result);
        }
        public void myMul(double param1, double param2)
        {
            double result = param1 * param2;
            Console.WriteLine(" I am usring Mul()!");
            Console.WriteLine("  {0}*{1}={2}", param1, param2, result);
        }
        public void myDiv(double param1, double param2)
        {
            double result = param1 / param2;
            Console.WriteLine(" I am usring Del()!");
            Console.WriteLine("  {0}/{1}={2}", param1, param2, result);
        }
    }
    class DelegateEntry
    {
        static void Main(string[] args)
        {
            Console.WriteLine(" Delegate tesing begin .....");
            DelegateTest delegateTest = new DelegateTest();
            myDelegate delegateHandleAdd= new myDelegate(delegateTest.myAdd);
            myDelegate delegateHandleSub = new myDelegate(delegateTest.mySub);
            myDelegate delegateHandleMul = new myDelegate(delegateTest.myMul);
            myDelegate delegateHandleDiv = new myDelegate(delegateTest.myDiv);
            if (delegateHandleAdd != null)
            {
                delegateHandleAdd(5,3);
            }
            Console.WriteLine("-----------------------------------------------------------------------------");
            if (delegateHandleSub != null)
            {
                delegateHandleSub(5, 3);
            }
            if (delegateHandleMul != null)
            {
                delegateHandleMul(5, 3);
            }
            Console.WriteLine("-----------------------------------------------------------------------------");
            if (delegateHandleDiv != null)
            {
                delegateHandleDiv(5, 3);
            }            myDelegate delegateCalculate = null;
            delegateCalculate += delegateHandleAdd ;
            Console.WriteLine("/n-----------------------------------------------------------------------------");
            Console.WriteLine(" I am using  [ delegateCalculate += delegateHandleAdd; ]");
            delegateCalculate(5, 3);            delegateCalculate += delegateHandleSub;
            Console.WriteLine("/n-----------------------------------------------------------------------------");
            Console.WriteLine(" I am using  [ delegateCalculate += delegateHandleSub; ]");
            delegateCalculate(5, 3);            delegateCalculate += delegateHandleMul;
            Console.WriteLine("/n-----------------------------------------------------------------------------");
            Console.WriteLine(" I am using  [ delegateCalculate += delegateHandleMul; ]");
            delegateCalculate(5, 3);            delegateCalculate += delegateHandleDiv;
            Console.WriteLine("/n-----------------------------------------------------------------------------");
            Console.WriteLine(" I am using  [ delegateCalculate += delegateHandleDiv; ]");
            delegateCalculate(5, 3);            Delegate[] delegateArray = delegateCalculate.GetInvocationList();
            Console.WriteLine("/n-----------------------------------------------------------------------------");
            Console.WriteLine(" I am using  [ delegateCalculate.GetInvocationList(); ]");
            Console.WriteLine("/n I have using  these methods :/n");    
            foreach (Delegate delgt in delegateArray)
            {
                Console.WriteLine(delgt.Method.GetBaseDefinition());
            }            delegateCalculate -= delegateHandleAdd;
            Console.WriteLine("/n-----------------------------------------------------------------------------");
            Console.WriteLine(" I am using  [ delegateCalculate -= delegateHandleAdd; ]");
            delegateCalculate(5, 3);            delegateCalculate -= delegateHandleSub;
            Console.WriteLine("/n-----------------------------------------------------------------------------");
            Console.WriteLine(" I am using  [ delegateCalculate -= delegateHandleSub; ]");
            delegateCalculate(5, 3);            delegateCalculate -= delegateHandleMul;
            Console.WriteLine("/n-----------------------------------------------------------------------------");
            Console.WriteLine(" I am using  [ delegateCalculate -= delegateHandleMul; ]");
            delegateCalculate(5, 3);            delegateCalculate -= delegateHandleDiv;
            Console.WriteLine("/n-----------------------------------------------------------------------------");
            Console.WriteLine(" I am using  [ delegateCalculate -= delegateHandleDiv; ]");
                        
            Console.WriteLine(" Delegate tesing end .....");
            Console.ReadLine();        }
    }
}