using System; using System.Collections.Generic; using System.Text; using System.Threading.Tasks; namespace HISP.Game.Services { public class Book { private static List libaryBooks = new List(); public static Book[] LibaryBooks { get { return libaryBooks.ToArray(); } } public int Id; public string Title; public string Author; public string Text; public Book(int id, string title, string author, string text) { Id = id; Title = title; Author = author; Text = text; libaryBooks.Add(this); } public static bool BookExists(int id) { try { GetBookById(id); return true; } catch(KeyNotFoundException) { return false; } } public static Book GetBookById(int id) { foreach(Book libaryBook in LibaryBooks) { if (libaryBook.Id == id) return libaryBook; } throw new KeyNotFoundException("no book with id: " + id.ToString() + " found."); } } }