C# Security 常用加密方法(针对string 的处理)

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

namespace StringHandling
{
/// <summary>
/// String encrypt/decrypt.
/// </summary>
public class Security
{
/// <summary>
/// MD5 encrypt.
/// </summary>
/// <param name="passWord">String to encrypt</param>
/// <returns>String encrypted</returns>
public static string Md5(string passWord)
{
Byte[] clearBytes = new UnicodeEncoding().GetBytes(passWord);
Byte[] hashedBytes = ((HashAlgorithm)CryptoConfig.CreateFromName("MD5")).ComputeHash(clearBytes);
return BitConverter.ToString(hashedBytes).Replace("-", "");
}

/// <summary>
/// SHA1 encrypt.
/// </summary>
/// <param name="passWord">String to encrypt</param>
/// <returns>String encrypted</returns>
public static string Sha1(string passWord)
{
Byte[] clearBytes = new UnicodeEncoding().GetBytes(passWord);
Byte[] hashedBytes = ((HashAlgorithm)CryptoConfig.CreateFromName("SHA1")).ComputeHash(clearBytes);
return BitConverter.ToString(hashedBytes);
}

/// <summary>
/// Rijndael(AES) Encrypt.
/// </summary>
/// <param name="source">Message to encrypt</param>
/// <param name="aesKey">Key</param>
/// <returns>Message encrypted</returns>
public static string AesEncrypt(string source, string aesKey)
{
byte[] bytIn = Encoding.UTF8.GetBytes(source);

//Bulid the Rijndael Key.
byte[] bKey = new byte[32];
Array.Copy(Encoding.UTF8.GetBytes(aesKey.PadRight(bKey.Length)), bKey, bKey.Length);

//Build the vector.
string aesIV = "KnXmC0KXxB3aQ4Hb";
byte[] bVector = new byte[16];
Array.Copy(Encoding.UTF8.GetBytes(aesIV.PadRight(bVector.Length)), bVector, bVector.Length);

//Create the Rijndael Object.
Rijndael aes = Rijndael.Create();

using (MemoryStream mStream = new MemoryStream())
{
using (CryptoStream cStream = new CryptoStream(mStream,
aes.CreateEncryptor(bKey, bVector),
CryptoStreamMode.Write))
{
cStream.Write(bytIn, 0, bytIn.Length);
cStream.FlushFinalBlock();
return Convert.ToBase64String(mStream.ToArray());
}
}
}

/// <summary>
/// Rijndael(AES) Decrypt.
/// </summary>
/// <param name="source">Message to decrypt</param>
/// <param name="aesKey">Key</param>
/// <returns>Message decrypted</returns>
public static string AesDecrypt(string source, string aesKey)
{
byte[] bytIn = Convert.FromBase64String(source);

//Bulid the Rijndael Key.
byte[] bKey = new byte[32];
Array.Copy(Encoding.UTF8.GetBytes(aesKey.PadRight(bKey.Length)), bKey, bKey.Length);

//Build the vector.
string aesIV = "KnXmC0KXxB3aQ4Hb";
byte[] bVector = new byte[16];
Array.Copy(Encoding.UTF8.GetBytes(aesIV.PadRight(bVector.Length)), bVector, bVector.Length);

//Create the Rijndael Object.
Rijndael aes = Rijndael.Create();

using (MemoryStream mStraem = new MemoryStream(bytIn))
{
using (CryptoStream cStream = new CryptoStream(mStraem,
aes.CreateDecryptor(bKey, bVector),
CryptoStreamMode.Read))
{
using (StreamReader sReader = new StreamReader(cStream))
{
return sReader.ReadToEnd();
}
}
}
}
}
}