c#编写可逆加密类(3DES加密)的教程

using System;
using System.Security;
using System.Security.Cryptography;
using System.IO;
using System.Text;
using System.Threading;
namespace TRIP3DES
{
/// <summary>
/// Class1 的摘要说明。
/// </summary>
public class dllEncrypt
{
//密钥
private const string sKey = "qJzGEh6hESZDVJeCnFPGuxzaiB7NLQM3";
//矢量，矢量可以为空
private const string sIV = "qcDY6X+aPLw=";
//构造一个对称算法
private SymmetricAlgorithm mCSP = new TripleDESCryptoServiceProvider();
public dllEncrypt(){}
#region public string EncryptString(string Value)
/// <summary>
/// 加密字符串
/// </summary>
/// <param name="Value">输入的字符串</param>
/// <returns>加密后的字符串</returns>
public string EncryptString(string Value)
{
ICryptoTransform ct;
MemoryStream ms;
CryptoStream cs;
byte[] byt;
mCSP.Key = Convert.FromBase64String(sKey);
mCSP.IV = Convert.FromBase64String(sIV);
//指定加密的运算模式
mCSP.Mode = System.Security.Cryptography.CipherMode.ECB;
//获取或设置加密算法的填充模式
mCSP.Padding = System.Security.Cryptography.PaddingMode.PKCS7;
ct = mCSP.CreateEncryptor(mCSP.Key, mCSP.IV);
byt = Encoding.UTF8.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());
}
#endregion
#region public string DecryptString(string Value)
/// <summary>
/// 解密字符串
/// </summary>
/// <param name="Value">加过密的字符串</param>
/// <returns>解密后的字符串</returns>
public string DecryptString(string Value)
{
ICryptoTransform ct;
MemoryStream ms;
CryptoStream cs;
byte[] byt;
mCSP.Key = Convert.FromBase64String(sKey);
mCSP.IV = Convert.FromBase64String(sIV);
mCSP.Mode = System.Security.Cryptography.CipherMode.ECB;
mCSP.Padding = System.Security.Cryptography.PaddingMode.PKCS7;
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());
}
#endregion
}
}