C# 檔案的加密/解密(DES) – jashliao部落格

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.IO;//FILE

using System.Security.Cryptography;//DESCryptoServiceProvider

namespace Console_CS_Encrypt_desDecrypt

{

    class Program

    {

        public
static void
desEncryptFile(string sourceFile, string encryptFile)

        {

            if
(string.IsNullOrEmpty(sourceFile) || string.IsNullOrEmpty(encryptFile))

            {

                return;

            }

            if
(!File.Exists(sourceFile))

            {

                return;

            }

            DESCryptoServiceProvider
des = new DESCryptoServiceProvider();

            byte[]
key =
Encoding.ASCII.GetBytes(“12345678”);

            byte[]
iv =
Encoding.ASCII.GetBytes(“87654321”);

            des.Key = key;

            des.IV = iv;

            using
(FileStream sourceStream = new FileStream(sourceFile,
FileMode.Open, FileAccess.Read))

            using
(FileStream encryptStream = new FileStream(encryptFile,
FileMode.Create, FileAccess.Write))

            {

                //檔E案¡Ñ加D[密ÓK

                byte[]
dataByteArray =
new byte[sourceStream.Length];

               
sourceStream.Read(dataByteArray, 0, dataByteArray.Length);

                using
(CryptoStream cs = new CryptoStream(encryptStream,
des.CreateEncryptor(),
CryptoStreamMode.Write))

                {

                    cs.Write(dataByteArray,
0, dataByteArray.Length);

                    cs.FlushFinalBlock();

                }

            }

        }

        public
static void
desDecryptFile(string encryptFile, string decryptFile)

        {

            if
(string.IsNullOrEmpty(encryptFile) || string.IsNullOrEmpty(decryptFile))

            {

                return;

            }

            if
(!File.Exists(encryptFile))

            {

                return;

            }

            DESCryptoServiceProvider
des = new DESCryptoServiceProvider();

            byte[]
key =
Encoding.ASCII.GetBytes(“12345678”);

            byte[]
iv =
Encoding.ASCII.GetBytes(“87654321”);

            des.Key = key;

            des.IV = iv;

            using
(FileStream encryptStream = new FileStream(encryptFile,
FileMode.Open, FileAccess.Read))

            using
(FileStream decryptStream = new FileStream(decryptFile,
FileMode.Create, FileAccess.Write))

            {

                byte[]
dataByteArray =
new byte[encryptStream.Length];

               
encryptStream.Read(dataByteArray, 0, dataByteArray.Length);

                using
(CryptoStream cs = new CryptoStream(decryptStream,
des.CreateDecryptor(),
CryptoStreamMode.Write))

                {

                    cs.Write(dataByteArray,
0, dataByteArray.Length);

                    cs.FlushFinalBlock();

                }

            }

        }

        static
void Main(string[]
args)

        {

            string
sourceFile=“C:\\Users\\RD\\Desktop\\06.nsi”;

            string
encryptFile=“C:\\Users\\RD\\Desktop\\06_e.nsi”;

            string
decryptFile=“C:\\Users\\RD\\Desktop\\06_d.nsi”;

           
desEncryptFile(sourceFile,encryptFile);

            desDecryptFile(encryptFile,
decryptFile);

            Pause();

        }

        public static void Pause()

        {

            Console.Write(“Press any key to continue . . . “);

            Console.ReadKey(true);

        }

    }

}