DES加密

 string key = "hdyxsjtd";//密匙8个字符
        //加密
        public string JiaMi(string sourceString)
        {
            byte[] keyBytes = Encoding.UTF8.GetBytes(key);
            byte[] keyIV = keyBytes;
            byte[] inputByteArray = Encoding.UTF8.GetBytes(sourceString);
            DESCryptoServiceProvider desProvider = new DESCryptoServiceProvider();
            MemoryStream memStream = new MemoryStream();
            CryptoStream crypStream = new CryptoStream(memStream, desProvider.CreateEncryptor(keyBytes, keyIV), CryptoStreamMode.Write);
            crypStream.Write(inputByteArray, 0, inputByteArray.Length);
            crypStream.FlushFinalBlock();
            return Convert.ToBase64String(memStream.ToArray());
        }

        //解密的函数
        public string JieMi(string encryptString)
        {
            byte[] keyBytes = Encoding.UTF8.GetBytes(key);
            byte[] keyIV = keyBytes;
            byte[] inputByteArray = Convert.FromBase64String(encryptString);
            DESCryptoServiceProvider desProvider = new DESCryptoServiceProvider();
            MemoryStream memStream = new MemoryStream();
            CryptoStream crypStream = new CryptoStream(memStream, desProvider.CreateDecryptor(keyBytes, keyIV), CryptoStreamMode.Write);
            crypStream.Write(inputByteArray, 0, inputByteArray.Length);
            crypStream.FlushFinalBlock();
            return Encoding.UTF8.GetString(memStream.ToArray());
        }