MD5加密解密

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

///MD5加密
  public string MD5Encrypt(string    pToEncrypt,  string    sKey)
    {  
     DESCryptoServiceProvider    des  =  new    DESCryptoServiceProvider();  
   byte[]    inputByteArray  =    Encoding.Default.GetBytes(pToEncrypt);  
     des.Key  =    ASCIIEncoding.ASCII.GetBytes(sKey);  
     des.IV  =    ASCIIEncoding.ASCII.GetBytes(sKey);  
     MemoryStream    ms  =  new    MemoryStream();  
     CryptoStream    cs  =  new    CryptoStream(ms,    des.CreateEncryptor(),CryptoStreamMode.Write);  
     cs.Write(inputByteArray,  0,    inputByteArray.Length);  
     cs.FlushFinalBlock();  
     StringBuilder    ret  =  new    StringBuilder();  
   foreach(byte    b  in    ms.ToArray())  
     {  
      ret.AppendFormat("{0:X2}",    b);  
     }  
     ret.ToString();  
   return    ret.ToString();  


    }

  ///MD5解密
  public string MD5Decrypt(string    pToDecrypt,  string    sKey)
    { 
     DESCryptoServiceProvider    des  =  new    DESCryptoServiceProvider();  

   byte[]    inputByteArray  =  new  byte[pToDecrypt.Length  /  2];  
   for(int    x  =  0;    x  <    pToDecrypt.Length  /  2;    x++)  
     {  
    int    i  =    (Convert.ToInt32(pToDecrypt.Substring(x  *  2,  2),  16));  
      inputByteArray[x]  =    (byte)i;  
     }  

     des.Key  =    ASCIIEncoding.ASCII.GetBytes(sKey);  
     des.IV  =    ASCIIEncoding.ASCII.GetBytes(sKey);  
     MemoryStream    ms  =  new    MemoryStream();  
     CryptoStream    cs  =  new    CryptoStream(ms,    des.CreateDecryptor(),CryptoStreamMode.Write);  
     cs.Write(inputByteArray,  0,    inputByteArray.Length);  
     cs.FlushFinalBlock();  

     StringBuilder    ret  =  new    StringBuilder();  
             
   return    System.Text.Encoding.Default.GetString(ms.ToArray());  
    }


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using System;
using System.Text;
using System.Globalization;
using System.Security.Cryptography;
class DES
{
// 创建Key
public string GenerateKey()
{
DESCryptoServiceProvider desCrypto = (DESCryptoServiceProvider)DESCryptoServiceProvider.Create();
return ASCIIEncoding.ASCII.GetString(desCrypto.Key);
}
// 加密字符串
public string EncryptString(string sInputString, string sKey)
{
byte [] data = Encoding.UTF8.GetBytes(sInputString);
DESCryptoServiceProvider DES = new DESCryptoServiceProvider();
DES.Key = ASCIIEncoding.ASCII.GetBytes(sKey);
DES.IV = ASCIIEncoding.ASCII.GetBytes(sKey);
ICryptoTransform desencrypt = DES.CreateEncryptor();
byte [] result = desencrypt.TransformFinalBlock(data, 0, data.Length);
return BitConverter.ToString(result);
}
// 解密字符串
public string DecryptString(string sInputString, string sKey)
{
string [] sInput = sInputString.Split("-".ToCharArray());
byte [] data = new byte[sInput.Length];
for(int i = 0; i < sInput.Length; i++)
{
data[i] = byte.Parse(sInput[i], NumberStyles.HexNumber);
}
DESCryptoServiceProvider DES = new DESCryptoServiceProvider();
DES.Key = ASCIIEncoding.ASCII.GetBytes(sKey);
DES.IV = ASCIIEncoding.ASCII.GetBytes(sKey);
ICryptoTransform desencrypt = DES.CreateDecryptor();
byte [] result = desencrypt.TransformFinalBlock(data, 0, data.Length);
return Encoding.UTF8.GetString(result);
}
}
class Test
{
static void Main()
{
DES des = new DES();
string key = des.GenerateKey();
string s0 = "中国软件 - csdn.net";
string s1 = des.EncryptString(s0, key);
string s2 = des.DecryptString(s1, key);
Console.WriteLine("原串: [{0}]", s0);
Console.WriteLine("加密: [{0}]", s1);
Console.WriteLine("解密: [{0}]", s2);
}
}
/* 程序输出:
原串: [中国软件 - csdn.net]
加密: [E8-30-D0-F2-2F-66-52-14-45-9A-DC-C5-85-E7-62-9B-AD-B7-82-CF-A8-0A-59-77]
解密: [中国软件 - csdn.net]
*/