用C#实现的数据加密(一) —— 对称加密算法

以下是关于对称加密算法的C#实现代码，大家可以根据需要更改不同的算法，文中以Rijndael算法为例：

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

namespace DataCrypto
{
/// <summary>
/// 对称加密算法类
/// </summary>
public class SymmetricMethod
{

private SymmetricAlgorithm mobjCryptoService;
private string Key;
/// <summary>
/// 对称加密类的构造函数
/// </summary>
public SymmetricMethod()
{
mobjCryptoService = new RijndaelManaged();
Key = "Guz(％&hj7x89H$yuBI0456FtmaT5&fvHUFCy76*h％(HilJ$lhj!y6&(*jkP87jH7";
}
/// <summary>
/// 获得密钥
/// </summary>
/// <returns>密钥</returns>
private byte[] GetLegalKey()
{
string sTemp = Key;
mobjCryptoService.GenerateKey();
byte[] bytTemp = mobjCryptoService.Key;
int KeyLength = bytTemp.Length;
if (sTemp.Length > KeyLength)
sTemp = sTemp.Substring(0, KeyLength);
else if (sTemp.Length < KeyLength)
sTemp = sTemp.PadRight(KeyLength, );
return ASCIIEncoding.ASCII.GetBytes(sTemp);
}
/// <summary>
/// 获得初始向量IV
/// </summary>
/// <returns>初试向量IV</returns>
private byte[] GetLegalIV()
{
string sTemp = "E4ghj*Ghg7!rNIfb&95GUY86GfghUb#er57HBh(u％g6HJ($jhWk7&!hg4ui％$hjk";
mobjCryptoService.GenerateIV();
byte[] bytTemp = mobjCryptoService.IV;
int IVLength = bytTemp.Length;
if (sTemp.Length > IVLength)
sTemp = sTemp.Substring(0, IVLength);
else if (sTemp.Length < IVLength)
sTemp = sTemp.PadRight(IVLength, );
return ASCIIEncoding.ASCII.GetBytes(sTemp);
}
/// <summary>
/// 加密方法
/// </summary>
/// <param name="Source">待加密的串</param>
/// <returns>经过加密的串</returns>
public string Encrypto(string Source)
{
byte[] bytIn = UTF8Encoding.UTF8.GetBytes(Source);
MemoryStream ms = new MemoryStream();
mobjCryptoService.Key = GetLegalKey();
mobjCryptoService.IV = GetLegalIV();
ICryptoTransform encrypto = mobjCryptoService.CreateEncryptor();
CryptoStream cs = new CryptoStream(ms, encrypto, CryptoStreamMode.Write);
cs.Write(bytIn, 0, bytIn.Length);
cs.FlushFinalBlock();
ms.Close();
byte[] bytOut = ms.ToArray();
return Convert.ToBase64String(bytOut);
}
/// <summary>
/// 解密方法
/// </summary>
/// <param name="Source">待解密的串</param>
/// <returns>经过解密的串</returns>
public string Decrypto(string Source)
{
byte[] bytIn = Convert.FromBase64String(Source);
MemoryStream ms = new MemoryStream(bytIn, 0, bytIn.Length);
mobjCryptoService.Key = GetLegalKey();
mobjCryptoService.IV = GetLegalIV();
ICryptoTransform encrypto = mobjCryptoService.CreateDecryptor();
CryptoStream cs = new CryptoStream(ms, encrypto, CryptoStreamMode.Read);
StreamReader sr = new StreamReader(cs);
return sr.ReadToEnd();
}
}
}