C# 实现简单的图书管理系统（控制台版）

public class Book
{
    public int Id { get; set; }
    public string Title { get; set; } // 书名
    public string Author { get; set; } // 作者
    public decimal Price { get; set; } // 价格
    public string Category { get; set; } // 分类
    public override string ToString()
    {
        return $"ID：{Id} | 书名：{Title} | 作者：{Author} | 价格：{Price:C} | 分类：{Category}";
    }
}
public class BookManager
{
    private static List<Book> _books = new List<Book>();
    private static int _nextId = 1; // 自增ID
    // 添加图书
    public static void AddBook()
    {
        Book book = new Book();
        book.Id = _nextId++;
        Console.Write("请输入书名：");
        book.Title = Console.ReadLine()?.Trim() ?? "";
        Console.Write("请输入作者：");
        book.Author = Console.ReadLine()?.Trim() ?? "";
        Console.Write("请输入价格：");
        decimal.TryParse(Console.ReadLine()?.Trim(), out decimal price);
        book.Price = price;
        Console.Write("请输入分类：");
        book.Category = Console.ReadLine()?.Trim() ?? "";
        _books.Add(book);
        Console.WriteLine("图书添加成功！");
    }
    // 查询所有图书
    public static void QueryAllBooks()
    {
        if (_books.Count == 0)
        {
            Console.WriteLine("暂无图书信息！");
            return;
        }
        Console.WriteLine("=== 所有图书信息 ===");
        foreach (var book in _books)
        {
            Console.WriteLine(book);
        }
    }
    // 按书名查询图书
    public static void QueryBookByTitle()
    {
        Console.Write("请输入要查询的书名关键词：");
        string keyword = Console.ReadLine()?.Trim() ?? "";
        var result = _books.Where(b => b.Title.Contains(keyword, StringComparison.OrdinalIgnoreCase)).ToList();
        if (result.Count == 0)
        {
            Console.WriteLine("未找到匹配的图书！");
            return;
        }
        Console.WriteLine($"=== 找到 {result.Count} 本匹配图书 ===");
        foreach (var book in result)
        {
            Console.WriteLine(book);
        }
    }
    // 删除图书
    public static void DeleteBook()
    {
        Console.Write("请输入要删除的图书ID：");
        if (!int.TryParse(Console.ReadLine()?.Trim(), out int id))
        {
            Console.WriteLine("无效的ID！");
            return;
        }
        Book book = _books.FirstOrDefault(b => b.Id == id);
        if (book == null)
        {
            Console.WriteLine("未找到该ID的图书！");
            return;
        }
        _books.Remove(book);
        Console.WriteLine("图书删除成功！");
    }
    // 显示菜单
    public static void ShowMenu()
    {
        Console.WriteLine("\n=== 图书管理系统 ===");
        Console.WriteLine("1. 添加图书");
        Console.WriteLine("2. 查询所有图书");
        Console.WriteLine("3. 按书名查询图书");
        Console.WriteLine("4. 删除图书");
        Console.WriteLine("5. 退出系统");
        Console.Write("请选择操作（1-5）：");
    }
    public static void Main(string[] args)
    {
        while (true)
        {
            ShowMenu();
            string choice = Console.ReadLine()?.Trim() ?? "";
            switch (choice)
            {
                case "1":
                    AddBook();
                    break;
                case "2":
                    QueryAllBooks();
                    break;
                case "3":
                    QueryBookByTitle();
                    break;
                case "4":
                    DeleteBook();
                    break;
                case "5":
                    Console.WriteLine("退出系统！");
                    return;
                default:
                    Console.WriteLine("无效操作，请重新选择！");
                    break;
            }
        }
    }
}