如何从C＃中的二进制文件读取2D int数组？

Question

I have a 2D integer array to store x,y coordinates. I checked out a few functions to write 2D array into a file but cannot find anything that is able to read that binary file on load and push it into a new 2 dimensional integer array.

This is my world generator function which saves it to the file:

public WorldGenerator()
{
    int worldSizeX = 100;
    int worldSizeY = 100;
    int[,] world = new int[worldSizeX*worldSizeY, 2];

    Logger.log("Generating world...");

    for(int x = 0; x < worldSizeX; x++)
    {
        for(int y = 0; y < 2; y++)
        {
            System.Random random = new System.Random();
            int itemID = random.Next(0, 1);

            world[x, y] = itemID;
        }
    }

    FileStream fs = new FileStream(Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData) + "/ConsoleGame/world/default.wd", FileMode.OpenOrCreate, FileAccess.Write);
    BinaryWriter bw = new BinaryWriter(fs);

    for (int x = 0; x < worldSizeX; x++)
    {
        for (int y = 0; y < 2; y++)
        {
            bw.Write(world[x, y]);
        }
    }

    bw.Close();
    fs.Close();
    Logger.log("World generated.");
}

Any good idea that could work for reading this file in? I should get back a 2D integer array and world[0,0] should get me the itemid. I am new to c# and this would be just a basic console application. I have also seen others answering similar questions but none of them are worked for me yet. Maybe because this save function is wrong or something else.

EDIT:

Here is how I load the file:

using (var filestream = File.Open(Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData) + "/ConsoleGame/world/default.wd", FileMode.Open))
using (var binaryStream = new BinaryReader(filestream))
{
    while (binaryStream.PeekChar() != -1)
    {
        Console.WriteLine(binaryStream.ReadInt32());
    }
}

Answer 1

need Newtonsoft.Json

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Newtonsoft.Json;

namespace ConsoleApp18
{
    class Program
    {
        static void Main(string[] args)
        {
            int worldSizeX = 100;
            int worldSizeY = 100;

            int[,] world = new int[worldSizeX * worldSizeY, 2];

            System.Random random = new System.Random();

            for (int x = 0; x < worldSizeX; x++)
            {
                for (int y = 0; y < 2; y++)
                {

                    int itemID = random.Next(0, 2);
                    world[x, y] = itemID;
                }
            }


            string json = JsonConvert.SerializeObject(world, Formatting.Indented);
            System.IO.File.WriteAllText("WriteText.txt", json);

            string text = System.IO.File.ReadAllText("WriteText.txt");
            int[,] deserialized = JsonConvert.DeserializeObject<int[,]>(text);

            //use "deserialized"

        }



    }

}

Answer 2

What you need is called "Serialization". Start with the simple builtin binary serializer .

Serializable attribute does the magic here.

By the moment you'll realize it is not the best option, you'll be able to use something more suiting your needs, like proto-buf .

I've also changed ints to shorts in your example. I doubt you need 32 bits for each world cell, so we can save a bit of hard drive space.

[Serializable]
public class WorldState
{
    public short[,] Items { get; set; }

    public void Save(string filename)
    {
        if (filename == null) throw new ArgumentNullException(nameof(filename));

        using (var file = File.Create(filename))
        {
            var serializer = new BinaryFormatter();
            serializer.Serialize(file, this);
        }
    }

    public static WorldState Load(string filename)
    {
        if (filename == null) throw new ArgumentNullException(nameof(filename));
        if (!File.Exists(filename)) throw new FileNotFoundException("File not found", filename);

        using (var file = File.OpenRead(filename))
        {
            var serializer = new BinaryFormatter();
            return serializer.Deserialize(file) as WorldState;
        }
    }
}

public class WorldStateTests
{
    [Fact]
    public void CanSaveAndLoad()
    {
        var ws = new WorldState
        {
            Items = new short[,]
            {
                { 1, 2, 3, 4 },
                { 1, 2, 3, 4 },
                { 1, 2, 3, 4 },
                { 1, 2, 3, 4 }
            }
        };
        // save the world state to file. Find it and see what's inside 
        ws.Save("./ws.bin");

        // load the world back
        var loaded = WorldState.Load("./ws.bin");

        // check a new world state got loaded
        Assert.NotNull(loaded);
        // and it still has items
        Assert.NotEmpty(loaded.Items);
        // and the items are the same as we saved
        Assert.Equal(ws.Items, loaded.Items);
    }
}