視頻上看到的例子，對著視頻打了一遍代碼，測試失敗，上網搜索后改了一下測試成功，不知道為什么跟視頻上打的一樣的代碼視頻上測試的正確而我的測試出錯的，先不管了，先記下來，以備后用！

    
  /// <summary>字符串加解密
    /// 
    /// </summary>
    public class Encrypt
    {
        private SymmetricAlgorithm mCSP;
        private const string CIV = "oo*/^fsA";  //密鑰, 只能是8位
        private const string CKEY = "f123$dew"; //初始化向量， 只能是8位

        public Encrypt()
        {
            mCSP = new DESCryptoServiceProvider();
        }

        /// <summary>加密字符串
        /// 
        /// </summary>
        /// <param name="Value"></param>
        /// <returns></returns>
        public string EncryptString(string Value)
        {
            ICryptoTransform ct;
            MemoryStream ms;
            CryptoStream cs;
            byte[] byt;
            // 這里視頻上用的是Convert.FromBase64String(CKEY/CIV),但是我用的話總是出現錯誤，什么大小不對
            ct = mCSP.CreateEncryptor(Encoding.ASCII.GetBytes(CKEY), Encoding.ASCII.GetBytes(CIV));
            byt = Encoding.UTF8.GetBytes(Value);
            ms = new MemoryStream();
            cs = new CryptoStream(ms, ct, CryptoStreamMode.Write);
            cs.Write(byt, 0, byt.Length);
            cs.FlushFinalBlock();
            cs.Close();
            return Convert.ToBase64String(ms.ToArray());
        }

        /// <summary>解密字符串
        /// 
        /// </summary>
        /// <param name="Value"></param>
        /// <returns></returns>
        public string DecryptString(string Value)
        {
            ICryptoTransform ct;
            MemoryStream ms;
            CryptoStream cs;
            byte[] byt;
            ct = mCSP.CreateDecryptor(Encoding.ASCII.GetBytes(CKEY), Encoding.ASCII.GetBytes(CIV));
            byt = Convert.FromBase64String(Value);

            ms = new MemoryStream();
            cs = new CryptoStream(ms, ct, CryptoStreamMode.Write);
            cs.Write(byt, 0, byt.Length);
            cs.FlushFinalBlock();
            cs.Close();

            return Encoding.UTF8.GetString(ms.ToArray());
        }
    }

  

測試代碼：

    
        static void Main(string[] args)
        {
            Console.Write("請輸入要加密的字符串：");
            string str = Console.ReadLine();
            Console.WriteLine("加密后：" + new Encrypt().EncryptString(str));
            Console.ReadLine();

            Console.Write("請輸入要解密的字符串：");
            string str2 = Console.ReadLine();
            Console.WriteLine("解密后：" + new Encrypt().DecryptString(str2));
            Console.ReadLine();
        }

  

測試效果：

通過密鑰對字符串進行加解密（C#）