/// <summary>    /// AES对称加密解密类    /// </summary>    public class AESHelper    {        #region 成员变量        /// <summary>        /// 密钥        /// </summary>        private static string _passwd = "ihlih*0037JOHT*)(PIJY*(()JI^)IO%";        /// <summary>        /// 密钥位数        /// </summary>        private const int _passwdLength = 32;        /// <summary>        /// 运算模式        /// </summary>        private static CipherMode _cipherMode = CipherMode.ECB;        /// <summary>        /// 填充模式        /// </summary>        private static PaddingMode _paddingMode = PaddingMode.PKCS7;        /// <summary>        /// 字符串采用的编码        /// </summary>        private static Encoding _encoding = Encoding.UTF8;        #endregion        #region 辅助方法        /// <summary>        /// 获取byte密钥数据        /// </summary>        /// <param name="password">密码</param>        /// <returns></returns>        private static byte[] GetKeyArray(string password)        {            if (password == null)            {                password = string.Empty;            }            if (password.Length < _passwdLength)            {                password = password.PadRight(_passwdLength, ‘0‘);            }            else if (password.Length > _passwdLength)            {                password = password.Substring(0, _passwdLength);            }            return _encoding.GetBytes(password);        }        /// <summary>        /// 将字符数组转换成字符串        /// </summary>        /// <param name="inputData"></param>        /// <returns></returns>        private static string ConvertByteToString(byte[] inputData)        {            StringBuilder sb = new StringBuilder(inputData.Length * 2);            foreach (var b in inputData)            {                sb.Append(b.ToString("X2"));            }            return sb.ToString();        }        /// <summary>        /// 将字符串转换成字符数组        /// </summary>        /// <param name="inputString"></param>        /// <returns></returns>        private static byte[] ConvertStringToByte(string inputString)        {            if (inputString == null || inputString.Length < 2)            {                throw new ArgumentException();            }            if ((inputString.Length % 2) != 0)            {                inputString += " ";            }            int l = inputString.Length / 2;            byte[] result = new byte[l];            for (int i = 0; i < l; ++i)            {                result[i] = Convert.ToByte(inputString.Substring(2 * i, 2), 16);            }            return result;        }        #endregion        #region 加密        /// <summary>        /// 加密字节数据        /// </summary>        /// <param name="inputData">要加密的字节数据</param>        /// <param name="password">密码</param>        /// <returns></returns>        public static byte[] Encrypt(byte[] inputData, string password)        {            using (AesCryptoServiceProvider aes = new AesCryptoServiceProvider())            {                aes.Key = GetKeyArray(password);                aes.Mode = _cipherMode;                aes.Padding = _paddingMode;                ICryptoTransform transform = aes.CreateEncryptor();                byte[] data = http://www.mamicode.com/transform.TransformFinalBlock(inputData, 0, inputData.Length);                aes.Clear();                return data;            }        }        /// <summary>        /// 加密字符串(加密为16进制字符串)        /// </summary>        /// <param name="inputString">要加密的字符串</param>        /// <param name="password">密码</param>        /// <returns></returns>        public static string Encrypt(string inputString, string password)        {            if (string.IsNullOrWhiteSpace(inputString) || string.IsNullOrWhiteSpace(password))            {                return string.Empty;            }            byte[] toEncryptArray = _encoding.GetBytes(inputString);            byte[] result = Encrypt(toEncryptArray, password);            return ConvertByteToString(result);        }        /// <summary>        /// 字符串加密(加密为16进制字符串)        /// </summary>        /// <param name="inputString">需要加密的字符串</param>        /// <returns>加密后的字符串</returns>        public static string EncryptString(string inputString)        {            if (string.IsNullOrWhiteSpace(_passwd))            {                throw new ArgumentException("密钥不能为空");            }            return Encrypt(inputString, _passwd);        }        #endregion        #region 解密        /// <summary>        /// 解密字节数组        /// </summary>        /// <param name="inputData">要解密的字节数据</param>        /// <param name="password">密码</param>        /// <returns></returns>        public static byte[] Decrypt(byte[] inputData, string password)        {            using (AesCryptoServiceProvider aes = new AesCryptoServiceProvider())            {                aes.Key = GetKeyArray(password);                aes.Mode = _cipherMode;                aes.Padding = _paddingMode;                ICryptoTransform transform = aes.CreateDecryptor();                byte[] data = http://www.mamicode.com/null;                try                {                    data = transform.TransformFinalBlock(inputData, 0, inputData.Length);                }                catch                {                    return null;                }                aes.Clear();                return data;            }        }        /// <summary>        /// 解密16进制的字符串为字符串        /// </summary>        /// <param name="inputString">要解密的字符串</param>        /// <param name="password">密码</param>        /// <returns>字符串</returns>        public static string Decrypt(string inputString, string password)        {            if (string.IsNullOrWhiteSpace(inputString) || string.IsNullOrWhiteSpace(password))            {                return string.Empty;            }            byte[] toDecryptArray = ConvertStringToByte(inputString);            string decryptString = _encoding.GetString(Decrypt(toDecryptArray, password));            return decryptString;        }        /// <summary>        /// 解密16进制的字符串为字符串        /// </summary>        /// <param name="inputString">需要解密的字符串</param>        /// <returns>解密后的字符串</returns>        public static string DecryptString(string inputString)        {            if (string.IsNullOrWhiteSpace(_passwd))            {                throw new ArgumentException("密钥不能为空");            }            return Decrypt(inputString, _passwd);        }        #endregion    }