C#对文件的字节加密/解密-可逆

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.IO;
using System.Threading;

namespace 文件加密
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void btn_Encode_Click(object sender, EventArgs e)
        {
            Thread th1 = new Thread(new ThreadStart(EncodingFile));
            th1.Start();
        }
        private void EncodingFile()
        {
            string inf = @txt_source.Text;//源文件地址
            string outf = @txt_des.Text;//目的文件地址
            FileInfo fi = new FileInfo(inf);
           
progressBar1.Maximum = (int)fi.Length;
            using (FileStream outstream = new FileStream(@outf, FileMode.Create))
            {
                using (FileStream fs = new FileStream(@inf, FileMode.Open))
                {
                    byte[] bytes = new byte[1024 * 1024 * 10];//10MB
                    int readlength;
                    while ((readlength = fs.Read(bytes, 0, bytes.Length)) > 0)
                    {
                        for (int i = 0; i < readlength; i++)
                        {
                            bytes[i] = (byte)(byte.MaxValue - bytes[i]);
                        }
                       
                        outstream.Write(bytes, 0, readlength);
                       progressBar1.Value += readlength;
                    }
                }
            }
            MessageBox.Show("加密完成，重复此过程即可解密！");
        }
    }
}