.NET中DES加密算法的基本使用

//或?者?下?面?的?另?一?个?程?序?代?码?：?

using System;

using System.Security.Cryptography;

using System.IO;

using System.Text;

public class Test

{

    //加?密?

public string DesEncrypt(string strText, string strEncrKey) 

{ 

byte[] byKey=null; 

byte[] IV= {0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF}; 

try 

{ 

byKey = System.Text.Encoding.UTF8.GetBytes(strEncrKey.Substring(0,8)); 

DESCryptoServiceProvider des = new DESCryptoServiceProvider(); 

byte[] inputByteArray = Encoding.UTF8.GetBytes(strText); 

MemoryStream ms = new MemoryStream(); 

CryptoStream cs = new CryptoStream(ms, des.CreateEncryptor(byKey, IV), CryptoStreamMode.Write) ; 

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

cs.FlushFinalBlock(); 

return Convert.ToBase64String(ms.ToArray()); 

} 

catch(System.Exception error) 

{ 

MessageBox.Show(error.Message); 

return "error:" +error.Message+"\r"; 

} 

}

//解?密?函?数?

public string DesDecrypt(string strText,string sDecrKey) 

{ 

byte[] byKey = null; 

byte[] IV= {0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF}; 

byte[] inputByteArray = new Byte[strText.Length]; 

try 

{ 

byKey = System.Text.Encoding.UTF8.GetBytes(sDecrKey.Substring(0,8)); 

DESCryptoServiceProvider des = new DESCryptoServiceProvider(); 

inputByteArray = Convert.FromBase64String(strText); 

MemoryStream ms = new MemoryStream(); 

CryptoStream cs = new CryptoStream(ms, des.CreateDecryptor(byKey, IV), CryptoStreamMode.Write); 

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

cs.FlushFinalBlock(); 

System.Text.Encoding encoding = new System.Text.UTF8Encoding(); 

return encoding.GetString(ms.ToArray()); 

} 

catch(System.Exception error) 

{ 

MessageBox.Show(error.Message); 

return "error:"+error.Message+"\r"; 

} 

} 

public class EncryptStringDES 

{

    public static void Main(String[] args) {

        if (args.Length < 1) {

            Console.WriteLine("Usage: des_demo ", args[0]);

            return;

        }

        // 使?用?UTF8函?数?加?密?输?入?参?数?

        UTF8Encoding utf8Encoding = new UTF8Encoding();

        byte[] inputByteArray = utf8Encoding.GetBytes(args[0].ToCharArray());

        // 方?式?一?：?调?用?默?认?的?DES实?现?方?法?DES_CSP.

        DES des = DES.Create();

        // 方?式?二?：?直?接?使?用?DES_CSP()实?现?DES的?实?体?

        //DES_CSP DES = new DES_CSP();

        // 初?始?化?DES加?密?的?密?钥?和?一?个?随?机?的?、?比?特?的?初?始?化?向?量?(IV)

        Byte[] key = {0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef};

        Byte[] IV = {0x12, 0x34, 0x56, 0x78, 0x90, 0xab, 0xcd, 0xef};

        des.Key = key;

        des.IV = IV;

        // 建?立?加?密?流?

          SymmetricStreamEncryptor sse = des.CreateEncryptor();

        // 使?用?CryptoMemoryStream方?法?获?取?加?密?过?程?的?输?出?

        CryptoMemoryStream cms = new CryptoMemoryStream();

        // 将?SymmetricStreamEncryptor流?中?的?加?密?数?据?输?出?到?CryptoMemoryStream中?

        sse.SetSink(cms);

        // 加?密?完?毕?，?将?结?果?输?出?到?控?制?台?

        sse.Write(inputByteArray);

        sse.CloseStream();

        // 获?取?加?密?数?据?

        byte[] encryptedData = cms.Data;

        // 输?出?加?密?后?结?果?

        Console.WriteLine("加?密?结?果?：?");

        for (int i = 0; i < encryptedData.Length; i++) {

            Console.Write("{0:X2} ",encryptedData[i]);

        }

        Console.WriteLine();

        //上?面?演?示?了?如?何?进?行?加?密?，?下?面?演?示?如?何?进?行?解?密?

        SymmetricStreamDecryptor ssd = des.CreateDecryptor();

        cms = new CryptoMemoryStream();

        ssd.SetSink(cms);

        ssd.Write(encryptedData);

        ssd.CloseStream();

        byte[] decryptedData = cms.Data;

        char[] decryptedCharArray = utf8Encoding.GetChars(decryptedData);

        Console.WriteLine("解?密?后?数?据?：?");

        Console.Write(decryptedCharArray);

        Console.WriteLine();

    }

}