C# 如何使用BinaryReader并正确地将数据输入文件？

我正在做作业，我完全被卡住了！我试图做的是使用已经定义的输入，并使用saveDataTo（）方法将其保存到文件中，然后使用readDataFrom（）方法读取输入

我被第一部分难住了。我不确定是否必须先初始化Program.cs文件中的数据

我不知道，我被卡住了。下面是代码，希望能为我提供一些技巧

--编辑--

我可以为saveDataTo（）和readDataFrom（）方法添加说明：

saveDataTo（）方法采用BinaryWriter参数。方法 将书本对象的所有5个属性的值写入文件 与写入程序关联的流（关联在 程序类的Main（）方法）。不需要打开和关闭 此方法中的文件流和二进制编写器

readDataFrom（）方法采用BinaryReader参数。这个 方法从中读取Book对象的所有五个属性的值 与读取器关联的文件流（关联在 程序类的Main（）方法）。没有必要打开和关闭 关闭此方法中的文件流和二进制读取器

所以这给了我一个线索，我应该使用和分配属性保存在那里的文件

--编辑--

更新了那里的代码。我确实对保存到文件中的内容有问题。我没有被告知价格。为什么呢

ff.APublisherNameTitle  FirstNameLastName

Program.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.IO;

namespace Lab_7
{
    class Program
    {
        private const string FILE_NAME = "lab07.dat";

        static void Main(string[] args)
        {
            //char ask;

            /*
            do
            {
                Console.Write("Enter Book Title: ");
                publication.Title = Console.ReadLine();
                Console.Write("Enter Author's First Name: ");
                book.AuthorFirstName = Console.ReadLine();
                Console.Write("Enter Author's Last Name: ");
                book.AuthorLastName = Console.ReadLine();
                Console.Write("Enter Publisher's Name: ");
                publication.PublisherName = Console.ReadLine();
                Console.Write("Enter Book Price: $");
                publication.Price = float.Parse(Console.ReadLine());
                Console.Write("Would like to enter another book? [Y or N] ");
                ask = char.Parse(Console.ReadLine().ToUpper());
            }
            while (ask == char.Parse("Y"));
            */

            Book book = new Book();

            book.Price = 10.9F;
            book.Title = "Title";
            book.PublisherName = "PublisherName";
            book.AuthorFirstName = "FirstName";
            book.AuthorLastName = "LastName";

            FileStream fileStream = new FileStream(FILE_NAME, FileMode.OpenOrCreate);
            BinaryWriter write = new BinaryWriter(fileStream);
            book.saveDataTo(write);
            write.Close();

            fileStream = new FileStream(FILE_NAME, FileMode.Open, FileAccess.Read);
            BinaryReader read = new BinaryReader(fileStream);
            book.readDataFrom(read);
            read.Close();
        }
    }
}

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.IO;

namespace Lab_7
{
    class Publication
    {
        private float price;
        private string publisherName, title;

        public float Price
        {
            get
            {
                return price;
            }
            set
            {
                price = value;
            }
        }

        public string PublisherName
        {
            get
            {
                return publisherName;
            }
            set
            {
                publisherName = value;
            }
        }

        public string Title
        {
            get
            {
                return title;
            }
            set
            {
                title = value;
            }
        }

        public void display()
        {
            Console.WriteLine("{0}\n{1}\n{2}", title, publisherName, price);
        }
    }
}

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.IO;

namespace Lab_7
{
    class Book : Publication
    {
        private string authorFirstName, authorLastName;

        public string AuthorFirstName
        {
            get
            {
                return authorFirstName;
            }
            set
            {
                authorFirstName = value;
            }
        }

        public string AuthorLastName
        {
            get
            {
                return authorLastName;
            }
            set
            {
                authorLastName = value;
            }
        }

        public new void display()
        {
        }

        public string getAuthorName()
        {
            return authorFirstName + " " + authorLastName;
        }

        public void readDataFrom(BinaryReader r)
        {
            Price = r.ReadInt32();
            PublisherName = r.ReadString();
            Title = r.ReadString();
            authorFirstName = r.ReadString();
            authorLastName = r.ReadString();
        }

        public void saveDataTo(BinaryWriter w)
        {
            w.Write(base.Price);
            w.Write(base.PublisherName);
            w.Write(base.Title);
            w.Write(AuthorFirstName);
            w.Write(AuthorLastName);
        }
    }
}

Publication.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.IO;

namespace Lab_7
{
    class Program
    {
        private const string FILE_NAME = "lab07.dat";

        static void Main(string[] args)
        {
            //char ask;

            /*
            do
            {
                Console.Write("Enter Book Title: ");
                publication.Title = Console.ReadLine();
                Console.Write("Enter Author's First Name: ");
                book.AuthorFirstName = Console.ReadLine();
                Console.Write("Enter Author's Last Name: ");
                book.AuthorLastName = Console.ReadLine();
                Console.Write("Enter Publisher's Name: ");
                publication.PublisherName = Console.ReadLine();
                Console.Write("Enter Book Price: $");
                publication.Price = float.Parse(Console.ReadLine());
                Console.Write("Would like to enter another book? [Y or N] ");
                ask = char.Parse(Console.ReadLine().ToUpper());
            }
            while (ask == char.Parse("Y"));
            */

            Book book = new Book();

            book.Price = 10.9F;
            book.Title = "Title";
            book.PublisherName = "PublisherName";
            book.AuthorFirstName = "FirstName";
            book.AuthorLastName = "LastName";

            FileStream fileStream = new FileStream(FILE_NAME, FileMode.OpenOrCreate);
            BinaryWriter write = new BinaryWriter(fileStream);
            book.saveDataTo(write);
            write.Close();

            fileStream = new FileStream(FILE_NAME, FileMode.Open, FileAccess.Read);
            BinaryReader read = new BinaryReader(fileStream);
            book.readDataFrom(read);
            read.Close();
        }
    }
}

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.IO;

namespace Lab_7
{
    class Publication
    {
        private float price;
        private string publisherName, title;

        public float Price
        {
            get
            {
                return price;
            }
            set
            {
                price = value;
            }
        }

        public string PublisherName
        {
            get
            {
                return publisherName;
            }
            set
            {
                publisherName = value;
            }
        }

        public string Title
        {
            get
            {
                return title;
            }
            set
            {
                title = value;
            }
        }

        public void display()
        {
            Console.WriteLine("{0}\n{1}\n{2}", title, publisherName, price);
        }
    }
}

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.IO;

namespace Lab_7
{
    class Book : Publication
    {
        private string authorFirstName, authorLastName;

        public string AuthorFirstName
        {
            get
            {
                return authorFirstName;
            }
            set
            {
                authorFirstName = value;
            }
        }

        public string AuthorLastName
        {
            get
            {
                return authorLastName;
            }
            set
            {
                authorLastName = value;
            }
        }

        public new void display()
        {
        }

        public string getAuthorName()
        {
            return authorFirstName + " " + authorLastName;
        }

        public void readDataFrom(BinaryReader r)
        {
            Price = r.ReadInt32();
            PublisherName = r.ReadString();
            Title = r.ReadString();
            authorFirstName = r.ReadString();
            authorLastName = r.ReadString();
        }

        public void saveDataTo(BinaryWriter w)
        {
            w.Write(base.Price);
            w.Write(base.PublisherName);
            w.Write(base.Title);
            w.Write(AuthorFirstName);
            w.Write(AuthorLastName);
        }
    }
}

Book.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.IO;

namespace Lab_7
{
    class Program
    {
        private const string FILE_NAME = "lab07.dat";

        static void Main(string[] args)
        {
            //char ask;

            /*
            do
            {
                Console.Write("Enter Book Title: ");
                publication.Title = Console.ReadLine();
                Console.Write("Enter Author's First Name: ");
                book.AuthorFirstName = Console.ReadLine();
                Console.Write("Enter Author's Last Name: ");
                book.AuthorLastName = Console.ReadLine();
                Console.Write("Enter Publisher's Name: ");
                publication.PublisherName = Console.ReadLine();
                Console.Write("Enter Book Price: $");
                publication.Price = float.Parse(Console.ReadLine());
                Console.Write("Would like to enter another book? [Y or N] ");
                ask = char.Parse(Console.ReadLine().ToUpper());
            }
            while (ask == char.Parse("Y"));
            */

            Book book = new Book();

            book.Price = 10.9F;
            book.Title = "Title";
            book.PublisherName = "PublisherName";
            book.AuthorFirstName = "FirstName";
            book.AuthorLastName = "LastName";

            FileStream fileStream = new FileStream(FILE_NAME, FileMode.OpenOrCreate);
            BinaryWriter write = new BinaryWriter(fileStream);
            book.saveDataTo(write);
            write.Close();

            fileStream = new FileStream(FILE_NAME, FileMode.Open, FileAccess.Read);
            BinaryReader read = new BinaryReader(fileStream);
            book.readDataFrom(read);
            read.Close();
        }
    }
}

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.IO;

namespace Lab_7
{
    class Publication
    {
        private float price;
        private string publisherName, title;

        public float Price
        {
            get
            {
                return price;
            }
            set
            {
                price = value;
            }
        }

        public string PublisherName
        {
            get
            {
                return publisherName;
            }
            set
            {
                publisherName = value;
            }
        }

        public string Title
        {
            get
            {
                return title;
            }
            set
            {
                title = value;
            }
        }

        public void display()
        {
            Console.WriteLine("{0}\n{1}\n{2}", title, publisherName, price);
        }
    }
}

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.IO;

namespace Lab_7
{
    class Book : Publication
    {
        private string authorFirstName, authorLastName;

        public string AuthorFirstName
        {
            get
            {
                return authorFirstName;
            }
            set
            {
                authorFirstName = value;
            }
        }

        public string AuthorLastName
        {
            get
            {
                return authorLastName;
            }
            set
            {
                authorLastName = value;
            }
        }

        public new void display()
        {
        }

        public string getAuthorName()
        {
            return authorFirstName + " " + authorLastName;
        }

        public void readDataFrom(BinaryReader r)
        {
            Price = r.ReadInt32();
            PublisherName = r.ReadString();
            Title = r.ReadString();
            authorFirstName = r.ReadString();
            authorLastName = r.ReadString();
        }

        public void saveDataTo(BinaryWriter w)
        {
            w.Write(base.Price);
            w.Write(base.PublisherName);
            w.Write(base.Title);
            w.Write(AuthorFirstName);
            w.Write(AuthorLastName);
        }
    }
}

问候

---

HelpNeeder.

您是在问是在Program.cs还是Book.cs中定义值，对吗？好的，在Program.cs中定义值是可以的，您只需要确保在写入数据之前给出了所有的值

因此，由于该函数采用假定已预先初始化的BinaryWriter参数，因此应该可以：

public void saveDataTo(BinaryWriter w)
{
     w.Write(getAuthorName());
     //etc...
}

---

但是，请记住，在调用“保存数据”之前，您确实需要在某处（任何地方）定义所有信息。

如果要将参数分配给两个不同的对象，请参阅：

Publication publication = new Publication(); 
Book book = new Book(); 

两者都是驻留在内存中的单个实例

您必须将出版物引用到以下书籍：

Book book = new Book(); 
Publication publication = (Publication)book;

或者直接将当前分配给出版物的值分配给书籍，以便：

publication.PublisherName = "PublisherName"; 

变成

book.PublisherName = "PublisherName"; 

除此之外，您使用的是C#，而不是Java。按照惯例，用大写字母开始你的方法是很正常的（帕斯卡）

编辑

您现在在重新读取时显示了价格，因为您将其作为浮动字段（或双精度字段，看不到定义）写入，并将其作为整数读取

---

从r.ReadInt32（）更改；到r.ReadDouble（）；或者r.ReadSingle（）

好的，我想应该是这样的。我必须在Main（）中添加一些东西，以便BinaryReader（）知道文件流吗？看看Program.cs中的第47行，不需要它吗？第47行是哪个？您在其中设置了新的BinaryWriter？我在它前面添加了注释行抱歉，不是第47行。它在program.cs部分。您确实需要声明一个新的BinaryWriter，这样saveDateTo（）函数就可以实际将数据写入某些东西。噢！好啊我知道你在说什么。因为我继承了参数，所以我应该使用book对象而不是Publishing。太好了，它可以编译。如果我有更多的问题，我会发布更多的问题。我的教授坚持我们用camel case来表示方法和类的大小写。你的教授真的教了你一个糟糕的做法。。。我并不知道什么是最好的，但我坚信，让事情符合行业标准是很重要的，除此之外，作为开发人员，您应该决定如何编写代码，并更新我的答案以解决您的第二个问题。现在关于你的老师（主题外）。如果你认为你可以改进别人的工作，即使是乔恩·斯基特本人，那就试着去做吧！好的，如果它是Float，那么您所做的唯一更改是在第一行的readDataFrom中，从“Price=r.ReadIn32（）；”更改为“Price=r.ReadSingle（）；”