serialization (18-19).3

// класс публикация
using System;

namespace myloyorrr
{
    [Serializable]
    abstract public class Publication:IComparable<Publication>
    {
        public string title { get; set; }
        public string author { get; set; }

        public Publication(string title, string author)
        {
            this.title = title;
            this.author = author;
        }

        public override string ToString() // вывод данных на экран
        {
            return $"{title}, {author}";
        }

        public int CompareTo(Publication item) // является ли искомым
        {
            if(this.author == item.author)
            {
                return 0;
            }
            else
            {
                if(this.author[0] > item.author[0])
                {
                    return 1;
                }
                else
                {
                    return -1;
                }
            }

        }

        public bool IsName(string auth) //поиск имени
        {
            if (this.author == auth)
            {
                return true;
            }
            else
            {
                return false;
            }
        }
    }
}
// производный класс книга
using System;

namespace myloyorrr
{
    [Serializable]
    class Book: Publication
    {
        public int year { get; set; }
        public string edition { get; set; }

        public Book(string title, string author, int year, string edition):base(title, author)
        {
            this.year = year;
            this.edition = edition;
        }

        public override string ToString()
        {
            return $"{title}, {author}, {year}, {edition}";
        }
    }
}
// производный класс article
using System;

namespace myloyorrr
{
    [Serializable]
    class Article: Publication
    {
        public string JournalTitle { get; set; }
        public int number { get; set; }
        public int year { get; set; }

        public Article(string title, string author, string journalTitle, int number, int year):base(title, author)
        {
            JournalTitle = journalTitle;
            this.number = number;
            this.year = year;
        }

        public override string ToString()
        {
            return $"{title}, {author}, {JournalTitle}, {number}, {year}";
        }
    }
}
// производный класс EResource
using System;

namespace myloyorrr
{
    [Serializable]
    class EResource: Publication
    {
        public string link { get; set; }
        public string annotation { get; set; }

        public EResource(string title, string author, string link, string annotation):base(title, author)
        {
            this.link = link;
            this.annotation = annotation;
        }

        public override string ToString()
        {
            return $"{title}, {author}, {link}, {annotation}";
        }
    }
}

using System;
using System.IO;
using System.Runtime.Serialization.Formatters.Binary;
using System.Collections.Generic;
using System.Runtime.Serialization;

namespace myloyorrr
{
    class Program
    {
        static void Print(List<Publication> objects)
        {
            if (objects.Count == 0)
            {
                Console.WriteLine("Список пуст");
            }
            else
            {
                Console.WriteLine("Список объектов:");
                foreach (Publication publication in objects)
                {
                    //Console.Write(publication.title + " ");
                    //Console.WriteLine(publication.author);
                   // string h = publication.ToString();
                    Console.WriteLine(publication);

                }
            }
        }

        static void Main()
        {
            List<Publication> objects = new List<Publication>();

            BinaryFormatter formatter = new BinaryFormatter();

            using (FileStream f = new FileStream("C:/Настя/книит/in.dat",
               FileMode.OpenOrCreate))
            {
                if (f.Length != 0)
                {
                    objects = (List<Publication>)formatter.Deserialize(f);
                }
                else
                {
                    //objects.Add(new Book("1984", "Orwell", 2000, "52"));
                    //objects.Add(new Article("1984", "Orwell", "Magazine", 73, 2001));
                    //objects.Add(new EResource("sgu", "author", "sgu.ru", "annotation"));
                }
            }

            Print(objects);
            objects.Add(new Book("19841", "Orwell", 2000, "52"));
            objects.Add(new Article("19841", "Orwell", "Magazine", 73, 2001));
            objects.Add(new EResource("sgu1", "Author", "sgu.ru", "annotation"));

            Console.WriteLine("Поиск по фамилии автора:");

            for(int i = 0; i < objects.Count; i++)
            {
                if (objects[i].IsName("Author"))
                {
                    Console.WriteLine(objects[i]);
                }
            }

            Console.WriteLine();
            Console.WriteLine("сортировка");

            objects.Sort(delegate (Publication x, Publication y) { return x.CompareTo(y); });

            Print(objects);

            using (FileStream f = new FileStream("C:/Настя/книит/in.dat",
               FileMode.OpenOrCreate))
            {
                formatter.Serialize(f, objects);
            }


        }
    }
}