string str = "2018";string result1 = AESHelper.AesEncrypt(str);string result2 = AESHelper.AesDecrypt(result1);

 

namespace Demo{    /// 
    /// AES加密解密 助手类    /// CBC加密模式    /// 
    public class AESHelper    {        /// 
        /// 默认密钥-长度32位        /// 
        private const string Key = "32位";        /// 
        /// 默认向量-长度16位        /// 
        private const string Iv = "16位";        /// 
          /// AES加密          /// 
          /// 需要加密字符串          /// 
     
      加密后字符串
              public static string AesEncrypt(string str)        {            return Encrypt(str, Key);        }        /// 
          /// AES解密          /// 
          /// 需要解密字符串          /// 
     
      解密后字符串
               public static string AesDecrypt(string str)        {            return Decrypt(str, Key);        }        /// 
        ///  AES 加密        /// 
        /// 明文（待加密）        /// 密文        /// 
             private static string Encrypt(string str, string key)        {            if (string.IsNullOrEmpty(str)) return null;            Byte[] toEncryptArray = Encoding.UTF8.GetBytes(str);            RijndaelManaged rm = new RijndaelManaged            {                Key = Encoding.UTF8.GetBytes(key),                Mode = CipherMode.ECB,                Padding = PaddingMode.PKCS7,                IV = Encoding.UTF8.GetBytes(Iv)            };            ICryptoTransform cTransform = rm.CreateEncryptor();            Byte[] resultArray = cTransform.TransformFinalBlock(toEncryptArray, 0, toEncryptArray.Length);            return Convert.ToBase64String(resultArray, 0, resultArray.Length);        }        /// 
        ///  AES 解密        /// 
        /// 明文（待解密）        /// 密文        /// 
             private static string Decrypt(string str, string key)        {            if (string.IsNullOrEmpty(str)) return null;            Byte[] toEncryptArray = Convert.FromBase64String(str);            RijndaelManaged rm = new RijndaelManaged            {                Key = Encoding.UTF8.GetBytes(key),                Mode = CipherMode.ECB,                Padding = PaddingMode.PKCS7,                IV = Encoding.UTF8.GetBytes(Iv)            };            ICryptoTransform cTransform = rm.CreateDecryptor();            Byte[] resultArray = cTransform.TransformFinalBlock(toEncryptArray, 0, toEncryptArray.Length);            return Encoding.UTF8.GetString(resultArray);        }    }}

 

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