C# Online Compiler | .NET Fiddle

using System;
using System.IO;
using System.Runtime.Serialization;
using System.Runtime.Serialization.Formatters.Binary;
					
public class Program
{
	public static void Main(string[] args)
	{
		WriteFile();
		ReadFile();
	}
	
	public static void WriteFile()
	{
		Test test = new Test
		{
			P1 = 1,
			P2 = "2"
		};
		
		IFormatter formatter = new BinaryFormatter();
		Stream stream = new FileStream("MyFile.txt",
									   FileMode.Create,
									   FileAccess.Write, FileShare.None);
		formatter.Serialize(stream, test);
		stream.Close();
		Console.WriteLine("寫入成功");
	}
	
	public static void ReadFile()
	{
		Console.WriteLine("讀出內容");
		var fileStream = new FileStream(@"MyFile.txt", FileMode.Open, FileAccess.Read);
		IFormatter formatter = new BinaryFormatter();
		Test test = formatter.Deserialize(fileStream) as Test;
		Console.WriteLine(string.Format("P1：{0}\nP2：{1}",test.P1,test.P2));
	}
}

[Serializable]
public class Test
{
	public int P1 { get; set; }
	public string P2 { get; set; }
}

 
using System;
using System.IO;
using System.Runtime.Serialization;
using System.Runtime.Serialization.Formatters.Binary;
                    
public class Program
{
    public static void Main(string[] args)
    {
        WriteFile();
        ReadFile();
    }
    
    public static void WriteFile()
    {
        Test test = new Test
        {
            P1 = 1,
            P2 = "2"
        };
        
        IFormatter formatter = new BinaryFormatter();
        Stream stream = new FileStream("MyFile.txt",
                                       FileMode.Create,

Cached Result

2025/01/03 09:55:33
2025/01/03 09:55:33