[导入] C#MD5加密解密

也是抄别人的，用起来方便。
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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