【概念】
数据加密算法（Data Encryption Algorithm，DEA）是一种对称加密算法，很可能是使用最广泛的密钥系统，特别是在保护金融数据的安全中，最初开发的DEA是嵌入硬件中的。通常，自动取款机（Automated Teller Machine，ATM）都使用DEA。它出自IBM的研究工作【from baidu】
【部分代码实现】
#region DES加密/解密字符串 //默认密钥向量 private static byte[] Keys = { 0x11, 0x22, 0x33, 0x44, 0x55, 0xAA, 0xBB, 0xCC }; public static string EncryptDES(string encryptString) { string encryptKey = StringUtils.ConvertToStr(GetConfig("CryptDESKey"), "abcd");//GetConfig方法为从配置文件读区数据 return EncryptDES(encryptString, encryptKey); } /// /// DES加密字符串 /// /// 待加密的字符串 /// 加密密钥,要求为8位 /// 加密成功返回加密后的字符串，失败返回源串 public static string EncryptDES(string encryptString, string encryptKey) { try { byte[] rgbKey = Encoding.UTF8.GetBytes(encryptKey.Substring(0, 8)); byte[] rgbIV = Keys; byte[] inputByteArray = Encoding.UTF8.GetBytes(encryptString); DESCryptoServiceProvider dCSP = new DESCryptoServiceProvider(); MemoryStream mStream = new MemoryStream(); CryptoStream cStream = new CryptoStream(mStream, dCSP.CreateEncryptor(rgbKey, rgbIV), CryptoStreamMode.Write); cStream.Write(inputByteArray, 0, inputByteArray.Length); cStream.FlushFinalBlock(); return Convert.ToBase64String(mStream.ToArray()).Replace("+", "%20"); } catch (Exception ex) { return string.Empty; } } public static string DecryptDES(string decryptString) { string decryptKey = StringUtils.ConvertToStr(GetConfig("CryptDESKey"), "abcd"); return DecryptDES(decryptString, decryptKey); } /// /// DES解密字符串 /// /// 待解密的字符串 /// 解密密钥,要求为8位,和加密密钥相同 /// 解密成功返回解密后的字符串，失败返源串 public static string DecryptDES(string decryptString, string decryptKey) { try { byte[] rgbKey = Encoding.UTF8.GetBytes(decryptKey); byte[] rgbIV = Keys; byte[] inputByteArray = Convert.FromBase64String(decryptString.Replace(' ', '+')); DESCryptoServiceProvider DCSP = new DESCryptoServiceProvider(); MemoryStream mStream = new MemoryStream(); CryptoStream cStream = new CryptoStream(mStream, DCSP.CreateDecryptor(rgbKey, rgbIV), CryptoStreamMode.Write); cStream.Write(inputByteArray, 0, inputByteArray.Length); cStream.FlushFinalBlock(); return Encoding.UTF8.GetString(mStream.ToArray()); } catch (Exception ex) { WrLogger logger = new WrLogger(); logger.WriteException("App_Code.WebUtils.DecryptDES(string, string) Error, DecryptString:" + decryptString, ex); return string.Empty; } } #endregion 注：此日志仅留作以后查询。