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

namespace AnonymousDelegatesSample
{
    public class Book
    {
        public string Title;
        public decimal Price;
    }

    public class Person
    {
        public string Firstname;
        public string Lastname;
        public List<Book> BookList;
        public decimal Discount;
        public DiscountCalculator CalculationMethod;
    }

    public delegate decimal DiscountCalculator(decimal price);

    public class Example
    {
        private decimal CalculateDiscount(decimal price)
        {
            return price * new decimal(0.05);
        }

        public void ShowExample()
        {

            DiscountCalculator default_calc = 
                new DiscountCalculator(CalculateDiscount);
            DiscountCalculator specialcustomer_calc = 
                delegate(decimal price) 
                { 
                    return price * new decimal(0.09); 
                };

            Book book1 = new Book();
            book1.Title = "ASP.NET for dummies";
            book1.Price = new decimal(35.99);

            Book Book2 = new Book();
            Book2.Title = "C# for dummies";
            Book2.Price = new decimal(49.99);

            List<Book> bookList = new List<Book>();
            bookList.Add(book1);
            bookList.Add(Book2);

            List<Person> personList = new List<Person>();

            Person person1 = new Person();
            person1.Firstname = "Norbert";
            person1.Lastname = "Eder";
            person1.BookList = bookList;
            person1.CalculationMethod = specialcustomer_calc;
            personList.Add(person1);

            Person person2 = new Person();
            person2.Firstname = "Alf";
            person2.Lastname = "Dudldei";
            person2.BookList = bookList;
            person2.CalculationMethod = default_calc;
            personList.Add(person2);

            foreach (Person p in personList) 
            {
                decimal price = 0;
                foreach (Book b in p.BookList)
                    price += b.Price;

                p.Discount = p.CalculationMethod(price);

                Console.WriteLine(
                    String.Format("{0} {1}:t {2} discount", 
                        p.Firstname, 
                        p.Lastname, 
                        p.Discount.ToString())); 
            }

            Console.WriteLine("Press any key ...");
            Console.ReadKey();
        }
    }
}

public delegate decimal DiscountCalculator(decimal price);

DiscountCalculator default_calc = 
    new DiscountCalculator(CalculateDiscount);

DiscountCalculator default_calc = 
    new DiscountCalculatprivate decimal CalculateDiscount(decimal price)
{
    return price * new decimal(0.05);
}or(CalculateDiscount);

DiscountCalculator specialcustomer_calc = 
    delegate(decimal price) 
    { 
        return price * new decimal(0.09); 
    };