C#（二十）：图书管理需求实现

需求

完整代码

Program.cs

using System;

// Program.cs
namespace ConsoleAppDemo
{

    class MainClass
    {
        static void Main(string[] args)
        {

            // 解决打印中文乱码问题
            Console.OutputEncoding = System.Text.Encoding.UTF8;

            BookManager bm = BookManager.bookManager;

            for (int i = 0; i < 10; i++) {
                // 增加
                bool result = bm.AddBook(new Book("航海王", 100, new Author("尾田荣一郎", Sex.Male, 45)));

                if (result)
                {
                    Console.WriteLine("=========添加图书成功=========");
                }
                else
                {
                    Console.WriteLine("=========添加图书失败=========");
                }
            }

            // 查询所有
            foreach (Book item in bm.QueryAllBook())
            {
                if (item != null)
                {
                    Console.WriteLine("===========查询所有-start===========");
                    Console.WriteLine(item.name);
                    Console.WriteLine(item.price);
                    Console.WriteLine(item.author.name);
                    Console.WriteLine(item.author.sex);
                    Console.WriteLine(item.author.age);
                    Console.WriteLine("============查询所有-end============");
                }
            }

            // 根据图书名称查询
            foreach (Book item in bm.QueryBookName("航海王"))
            {
                if (item != null)
                {
                    Console.WriteLine("===========据书名查询-start===========");
                    Console.WriteLine(item.name);
                    Console.WriteLine(item.price);
                    Console.WriteLine(item.author.name);
                    Console.WriteLine(item.author.sex);
                    Console.WriteLine(item.author.age);
                    Console.WriteLine("============据书名查询-end============");
                }
            }

            // 根据作者姓名称查询
            foreach (Book item in bm.QueryAuthorName("尾田荣一郎"))
            {
                if (item != null)
                {
                    Console.WriteLine("===========据作者查询-start===========");
                    Console.WriteLine(item.name);
                    Console.WriteLine(item.price);
                    Console.WriteLine(item.author.name);
                    Console.WriteLine(item.author.sex);
                    Console.WriteLine(item.author.age);
                    Console.WriteLine("============据作者查询-end============");
                }
            }

            // 删除所有图书
            bool delResult = bm.DeleteAllBook();

            if (delResult)
            {
                Console.WriteLine("============删除成功============");
            }
            else
            {
                Console.WriteLine("============删除失败============");
            }

            // 查询所有
            foreach (Book item in bm.QueryAllBook())
            {
                if (item != null)
                {
                    Console.WriteLine("===========查询所有-start===========");
                    Console.WriteLine(item.name);
                    Console.WriteLine(item.price);
                    Console.WriteLine(item.author.name);
                    Console.WriteLine(item.author.sex);
                    Console.WriteLine(item.author.age);
                    Console.WriteLine("============查询所有-end============");
                }
            }

        }
    }
    
}

Data.cs

using System;

// Data.cs 数据
namespace ConsoleAppDemo
{

    /// <summary>
    /// 图书类
    /// </summary>
    class Book
    {
        public string name;         // 书名
        public double price;        // 书价
        public Author author;       // 作者信息

        public Book(string name, double price, Author author)
        {
            this.name = name;
            this.price = price;
            this.author = author;
        }
    }

    /// <summary>
    /// 性别 男 女
    /// </summary>
    enum Sex { Male, Female }

    /// <summary>
    /// 作者类
    /// </summary>
    class Author
    {
        public string name;         // 作者
        public Sex sex;             // 性别
        public uint age;            // 年龄

        public Author(string name, Sex sex, uint age)
        {
            this.name = name;
            this.sex = sex;
            this.age = age;
        }
    }

}

BookManager.cs

using System;

// BookManager.cs 数据管理类
namespace ConsoleAppDemo
{

    /// <summary>
    /// 单例 - 图书的管理类
    /// </summary>
    class BookManager
    {

        private BookManager() { }

        public static readonly BookManager bookManager = new BookManager();

        private static int capcity = 10;                            // 容量
        public static Book[] allBooks = new Book[capcity];          // 存储所有书籍
        private static int count = 0;                               // 记录存储书籍数量

        /// <summary>
        /// 添加图书
        /// </summary>
        /// <param name="book">图书信息</param>
        /// <returns>是否添加成功</returns>
        public bool AddBook(Book book)
        {
            if (count >= 10) return false;

            allBooks[count++] = book;

            return true;
        }

        /// <summary>
        /// 查询所有图书
        /// </summary>
        /// <returns>图书数组</returns>
        public Book[] QueryAllBook()
        {
            return allBooks;
        }

        /// <summary>
        /// 根据书名查询图书
        /// </summary>
        /// <param name="name">书名</param>
        /// <returns>图书数组</returns>
        public Book[] QueryBookName(string name)
        {

            int count = 0;
            Book[] book = new Book[capcity];

            foreach (Book item in allBooks)
            {
                if (item != null)
                {
                    if (item.name == name)
                    {
                        book[count++] = item;
                    }
                }
            }

            return book;
        }

        /// <summary>
        /// 根据作者查询图书
        /// </summary>
        /// <param name="name">作者</param>
        /// <returns>图书数组</returns>
        public Book[] QueryAuthorName(string name)
        {
            int count = 0;
            Book[] book = new Book[capcity];

            foreach (Book item in allBooks)
            {
                if (item != null)
                {
                    if (item.author.name == name)
                    {
                        book[count++] = item;
                    }
                }
            }

            return book;
        }

        /// <summary>
        /// 删除所有书籍
        /// </summary>
        /// <returns>是否删除成功</returns>
        public bool DeleteAllBook()
        {
            // 或者将每个数组中元素置为null
            for (int i = 0; i <= count; i++) {
                allBooks[i] = null;
            }
            //allBooks = new Book[capcity];
            count = 0;
            return true;
        }

    }

}