加密解密处理工具

一个简单的加密与解密工具代码，直接对文件进行加密与解密。

 

using System;
using System.Collections.Generic;
using System.Text;
using System.IO;
using System.Security.Cryptography;


public class EncryptTools
{
    /**//// <summary>
    /// 加密使用指定的密钥加密文件
    /// </summary>
    /// <param name="sInputFilename">需要加密的文件按</param>
    /// <param name="sOutputFilename">加密后的文件</param>
    /// <param name="sKey">密钥</param>
    public static void EncryptFile(string sInputFilename,
                        string sOutputFilename,
                        string sKey)
    {
        FileStream fsInput = new FileStream(sInputFilename,
                                            FileMode.Open,
                                            FileAccess.Read);

        FileStream fsEncrypted = new FileStream(sOutputFilename,
                                                FileMode.Create,
                                                FileAccess.Write);
        DESCryptoServiceProvider DES = new DESCryptoServiceProvider();
        DES.Key = ASCIIEncoding.ASCII.GetBytes(sKey);
        DES.IV = ASCIIEncoding.ASCII.GetBytes(sKey);
        ICryptoTransform desencrypt = DES.CreateEncryptor();
        CryptoStream cryptostream = new CryptoStream(fsEncrypted,
                                                     desencrypt,
                                                     CryptoStreamMode.Write);

        byte[] bytearrayinput = new byte[fsInput.Length];
        fsInput.Read(bytearrayinput, 0, bytearrayinput.Length);
        cryptostream.Write(bytearrayinput, 0, bytearrayinput.Length);
        cryptostream.Close();
        fsInput.Close();
        fsEncrypted.Close();
    }
    /**//// <summary>
    /// 解密指定的文件
    /// </summary>
    /// <param name="sInputFilename">需要解密的文件</param>
    /// <param name="sOutputFilename">解密的文件输出</param>
    /// <param name="sKey">密钥</param>
    public static void DecryptFile(string sInputFilename,
                            string sOutputFilename,
                            string sKey)
    {
        DESCryptoServiceProvider DES = new DESCryptoServiceProvider();
        //A 64 bit key and IV is required for this provider.
        //Set secret key For DES algorithm.
        DES.Key = ASCIIEncoding.ASCII.GetBytes(sKey);
        //Set initialization vector.
        DES.IV = ASCIIEncoding.ASCII.GetBytes(sKey);

        //Create a file stream to read the encrypted file back.
        FileStream fsread = new FileStream(sInputFilename, FileMode.Open, FileAccess.Read);
        //Create a DES decryptor from the DES instance.
        ICryptoTransform desdecrypt = DES.CreateDecryptor();
        FileStream fsDecrypted = new FileStream(sOutputFilename, FileMode.Create, FileAccess.Write);
        //Create crypto stream set to read and do a DES decryption transform on incoming bytes.
        CryptoStream cryptostreamDecr = new CryptoStream(fsDecrypted, desdecrypt, CryptoStreamMode.Write);

        //Print out the contents of the decrypted file.
        byte[] bytearrayinput = new byte[fsread.Length];
        fsread.Read(bytearrayinput, 0, bytearrayinput.Length);
        cryptostreamDecr.Write(bytearrayinput, 0, bytearrayinput.Length);
        cryptostreamDecr.Close();
        fsread.Close();
        fsDecrypted.Close();
    }
}