C#使用AES加密解密的简单介绍

AES 算法是基于置换和代替的。置换是数据的重新排列，而代替是用一个单元数据替换另一个。AES 使用了几种不同的技术来实现置换和替换。

以下是我自己用c#研究出来算法Code：

        /// <summary>
        ///  AES 加密
        /// </summary>
        /// <param name="str"></param>
        /// <param name="key"></param>
        /// <returns></returns>
        public static string AesEncrypt(string str, string key)
        {
            try
            {
                if (string.IsNullOrEmpty(str)) return null;
                Byte[] toEncryptArray = Encoding.UTF8.GetBytes(str);

                System.Security.Cryptography.RijndaelManaged rm = new System.Security.Cryptography.RijndaelManaged
                {
                    Key = Encoding.UTF8.GetBytes(key),
                    Mode = System.Security.Cryptography.CipherMode.ECB,
                    Padding = System.Security.Cryptography.PaddingMode.PKCS7
                };

                System.Security.Cryptography.ICryptoTransform cTransform = rm.CreateEncryptor();
                Byte[] resultArray = cTransform.TransformFinalBlock(toEncryptArray, 0, toEncryptArray.Length);

                return Convert.ToBase64String(resultArray, 0, resultArray.Length);
            }
            catch (Exception ex)
            {
                LogHelper.WriteLog(LogFile.Error, ex.Message);
                return "";
            }
        }

        /// <summary>
        ///  AES 解密
        /// </summary>
        /// <param name="str"></param>
        /// <param name="key"></param>
        /// <returns></returns>
        public static string AesDecrypt(string str, string key)
        {
            try
            {
                if (string.IsNullOrEmpty(str)) return null;
                Byte[] toEncryptArray = Convert.FromBase64String(str);

                System.Security.Cryptography.RijndaelManaged rm = new System.Security.Cryptography.RijndaelManaged
                {
                    Key = Encoding.UTF8.GetBytes(key),
                    Mode = System.Security.Cryptography.CipherMode.ECB,
                    Padding = System.Security.Cryptography.PaddingMode.PKCS7
                };

                System.Security.Cryptography.ICryptoTransform cTransform = rm.CreateDecryptor();
                Byte[] resultArray = cTransform.TransformFinalBlock(toEncryptArray, 0, toEncryptArray.Length);

                return Encoding.UTF8.GetString(resultArray);
            }
            catch (Exception ex)
            {
                LogHelper.WriteLog(LogFile.Error, ex.Message);
                return "";
            }
        }