asp.net中实现MD5加密、解密的方法

/*用法
protected void Page_Load(object sender, EventArgs e)
{
//加密
this.Title = CEncrypt.DesEncrypt("pwd", CEncrypt.Key);
this.Title += CEncrypt.DesDecrypt(this.Title, CEncrypt.Key);
Response.Write(CEncrypt.DesDecrypt("gAYyhdLQunc=", CEncrypt.Key));
}
*/
using System;
using System.IO;
using System.Text;
using System.Security.Cryptography;
using System.Web;

namespace YD.Common
{
/// <summary>
/// 加密码类
/// </summary>
public class CEncrypt
{
/// <summary>
/// 加密
/// </summary>
/// <param name="inputString"></param>
/// <returns></returns>
public static string DesEncrypt(string inputString)
{
return DesEncrypt(inputString, Key);
}
/// <summary>
/// 解密
/// </summary>
/// <param name="inputString"></param>
/// <returns></returns>
public static string DesDecrypt(string inputString)
{
return DesDecrypt(inputString, Key);
}
/// <summary>
/// 密匙
/// </summary>
private static string Key
{
get
{
return "hongye10";
}
}
/// <summary>
/// 加密字符串
/// 注意:密钥必须为８位
/// </summary>
/// <param name="strText">字符串</param>
/// <param name="encryptKey">密钥</param>
/// <param name="encryptKey">返回加密后的字符串</param>
public static string DesEncrypt(string inputString, string encryptKey)
{
byte[] byKey = null;
byte[] IV = { 0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF };
try
{
byKey = System.Text.Encoding.UTF8.GetBytes(encryptKey.Substring(0, 8));
DESCryptoServiceProvider des = new DESCryptoServiceProvider();
byte[] inputByteArray = Encoding.UTF8.GetBytes(inputString);
MemoryStream ms = new MemoryStream();
CryptoStream cs = new CryptoStream(ms, des.CreateEncryptor(byKey, IV), CryptoStreamMode.Write);
cs.Write(inputByteArray, 0, inputByteArray.Length);
cs.FlushFinalBlock();
return Convert.ToBase64String(ms.ToArray());
}
catch (System.Exception error)
{
//return error.Message;
return null;
}
}
/// <summary>
/// 解密字符串
/// </summary>
/// <param name="this.inputString">加了密的字符串</param>
/// <param name="decryptKey">密钥</param>
/// <param name="decryptKey">返回解密后的字符串</param>
public static string DesDecrypt(string inputString, string decryptKey)
{
byte[] byKey = null;
byte[] IV = { 0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF };
byte[] inputByteArray = new Byte[inputString.Length];
try
{
byKey = System.Text.Encoding.UTF8.GetBytes(decryptKey.Substring(0, 8));
DESCryptoServiceProvider des = new DESCryptoServiceProvider();
inputByteArray = Convert.FromBase64String(inputString);
MemoryStream ms = new MemoryStream();
CryptoStream cs = new CryptoStream(ms, des.CreateDecryptor(byKey, IV), CryptoStreamMode.Write);
cs.Write(inputByteArray, 0, inputByteArray.Length);
cs.FlushFinalBlock();
System.Text.Encoding encoding = new System.Text.UTF8Encoding();
return encoding.GetString(ms.ToArray());
}
catch (System.Exception error)
{
//return error.Message;
return null;
}
}
}
}