using System;

using System.Collections.Generic;

using System.ComponentModel;

using System.Data;

using System.Drawing;

using System.IO;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

using System.Windows.Forms;

namespace 文件加密

{

    public partial class Form1 : Form

    {

        public Form1()

        {

            InitializeComponent();

        }

        private void btnFile_Click(object sender, EventArgs e)

        {

            OpenFileDialog ofd = new OpenFileDialog();

            ofd.Title = "请选择要加密的文件";

            //初始路径

            ofd.InitialDirectory = @"C:\Users\home\Desktop";

            ofd.Filter = "所有文件|*.*";

            ofd.ShowDialog();

            txtFile.Text = ofd.FileName;

        }

        private void btnCode_Click(object sender, EventArgs e)

        {

            SaveFileDialog sfd = new SaveFileDialog();

            sfd.Title = "请选择要保存文件的路径";

            sfd.InitialDirectory = @"C:\Users\home\Desktop";

            sfd.Filter = "所有文件|*.*";

            sfd.ShowDialog();

            txtCodeFile.Text = sfd.FileName;

            //调用方法

            MakeCode( "加密");

        }

        private void btnUnCode_Click(object sender, EventArgs e)

        {

            SaveFileDialog sfd = new SaveFileDialog();

            sfd.Title = "请选择要保存文件的路径";

            sfd.InitialDirectory = @"C:\Users\home\Desktop";

            sfd.Filter = "所有文件|*.*";

            sfd.ShowDialog();

            txtCodeFile.Text = sfd.FileName;

            //调用方法

            MakeCode("解密");

        }

        public void MakeCode(string content)

        {

            //1 先读取文件

            using (FileStream fsRead = new FileStream(txtFile.Text.Trim(), FileMode.OpenOrCreate, FileAccess.Read))

            {

                using (FileStream fsWrite = new FileStream(txtCodeFile.Text.Trim(), FileMode.OpenOrCreate, FileAccess.Write))

                {

                    //设置进度条

                    progressBar1.Maximum = (int)fsRead.Length;

                    byte[] buffer = new byte[ *  * ];

                    while (true)

                    {

                        int r = fsRead.Read(buffer, , buffer.Length);

                        if (r == )

                        {

                            break;

                        }

                        byte passWord = ;

                        if (byte.TryParse(txtPassword.Text.Trim(), out passWord)&& content.Equals("加密"))

                        {

                            for (int i = ; i < buffer.Length; i++)

                            {

                                buffer[i] += passWord;

                            }

                        }

                        if (byte.TryParse(txtPassword.Text.Trim(), out passWord) && content.Equals("解密"))

                        {

                            for (int i = ; i < buffer.Length; i++)

                            {

                                buffer[i] -= passWord;

                            }

                        }

                        fsWrite.Write(buffer, , r);

                        progressBar1.Value = (int)fsWrite.Length;

                    }

                }

                MessageBox.Show("保存成功!");

            }

        }

    }

}