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();
}
}
}
