C# 委托：把方法组合到一个数组中使用

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace ConsoleApplication1
{
    class MathOperations
    {
        public static double MultiplyByTwo(double value)
        {
            return value * 2;
        }

        public static double Square(double value)
        {
            return value * value;
        }
    }

    delegate double DoubleOpt(double x);

    class Program
    {
        public enum TimeOfDay
        {
            Morning = 0,
            Afternoons = 1,
            Evening = 2
        }

        static void Main(string[] args)
        {
            DoubleOpt[] opt = {
                                  MathOperations.MultiplyByTwo,
                                  MathOperations.Square
                              };

            for (int i = 0; i < opt.Length;i++ )
            {
                System.Console.WriteLine("Using Options [{0}]:",i);
                ProcessAndDisplayNumber(opt[i], 2.0);
                ProcessAndDisplayNumber(opt[i], 7.94);
                ProcessAndDisplayNumber(opt[i], 1.414);
                Console.WriteLine();
            }
        }

        static void ProcessAndDisplayNumber(DoubleOpt opt,double value)
        {
            double result = opt(value);
            System.Console.WriteLine("Value is {0}, result of operation is {1}",
                value,result);
        }
    }
}