C#中的3DES加密和MD5加密

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

namespace Interact.TeleSales
{
/// <summary>
/// DesCrypt 的摘要说明。
/// </summary>
public class DesCrypt
{
public DesCrypt()
{

}
private TripleDESCryptoServiceProvider mCSP = null;
private string sKey = "";
private string sIV = "";

public void Init(string key,string iv)
{
mCSP = new TripleDESCryptoServiceProvider();
mCSP.Mode = CipherMode.CBC;
mCSP.Padding = PaddingMode.PKCS7;

sKey = key;
sIV = iv;
byte[] byk = Encoding.ASCII.GetBytes(sKey);
mCSP.Key = byk;
byte[] byi = Encoding.ASCII.GetBytes(sIV);
mCSP.IV = byi;

}
//退款接口特别之处：文档为utf8，但是3des加密和md5加密使用gb2312来做
public string EncryptString(string Value)
{
return EncryptString(Value,"utf-8");
}
public string EncryptString(string Value,string encodingname)
{
ICryptoTransform ct;
MemoryStream ms;
CryptoStream cs;
byte[] byt;
ct = mCSP.CreateEncryptor(mCSP.Key, mCSP.IV);
//byt = Encoding.UTF8.GetBytes(Value);
Encoding enc = GetEncoding(encodingname);
byt = enc.GetBytes(Value);

ms = new MemoryStream();
cs = new CryptoStream(ms, ct, CryptoStreamMode.Write);
cs.Write(byt, 0, byt.Length);
cs.FlushFinalBlock();
cs.Close();
return Convert.ToBase64String(ms.ToArray());
}
public string DecryptString(string Value)
{
ICryptoTransform ct;
MemoryStream ms;
CryptoStream cs;
byte[] byt;
ct = mCSP.CreateDecryptor(mCSP.Key, mCSP.IV);
byt = Convert.FromBase64String(Value);
ms = new MemoryStream();
cs = new CryptoStream(ms, ct, CryptoStreamMode.Write);
cs.Write(byt, 0, byt.Length);
cs.FlushFinalBlock();
cs.Close();
return Encoding.UTF8.GetString(ms.ToArray());
}
public string GetMD5(string val)
{
string md5 = System.Web.Security.FormsAuthentication.HashPasswordForStoringInConfigFile(val, "MD5");

md5 = md5.ToUpper();
return md5;
}


/// <summary>
/// 生成MD5摘要
/// </summary>
/// <param name="p_Bytes"></param>
/// <returns></returns>
public string CryptoMD5(string str)
{
return CryptoMD5(str,"utf-8");
}
public string CryptoMD5(string str,string encodingname)
{
Encoding enc = GetEncoding(encodingname);
byte []bi = enc.GetBytes(str);

MD5 tmpMD5 = new MD5CryptoServiceProvider();
byte[] tmpResult = tmpMD5.ComputeHash(bi);
return ConvertToHex(tmpResult);
}
public string CryptoMD5(byte[] p_Bytes)
{
MD5 tmpMD5 = new MD5CryptoServiceProvider();
byte[] tmpResult = tmpMD5.ComputeHash(p_Bytes);
return ConvertToHex(tmpResult);
}
private string ConvertToHex(byte[] p_ResultBytes)
{
string rtnValue = string.Empty;
foreach (byte tmpEachByte in p_ResultBytes)
{
string tmpEachCode = Convert.ToString(tmpEachByte, 16);
if (tmpEachCode.Length == 1)
{
tmpEachCode = "0" + tmpEachCode;
}
rtnValue += tmpEachCode;
}
return rtnValue;
}
private Encoding GetEncoding(string encodingname)
{
Encoding enc = null;
try
{
enc = Encoding.GetEncoding(encodingname);
}
catch
{
enc = Encoding.UTF8;
}
return enc;
}
}
}