c# DeS 加密解密字符串

 

public static class DESSecurity

    {

        #region DES加密字符串

        /// <summary>

        /// DES加密方法

        /// </summary>

        /// <param name="plain">明文</param>

        /// <param name="key">密钥</param>

        /// <param name="iv">向量</param>

        /// <param name="isBase64">生成的密码是否用base64编码</param>

        /// <returns>密文</returns>

        public static String EncryptDES(string plain, byte[] rgbKey, byte[] rgbIV)

        {

            if (rgbKey.Length != 8) throw new ArgumentException("长度必须为8。", "rgbKey");

            if (rgbIV.Length != 8) throw new ArgumentException("长度必须为8。", "rgbIV");

            DESCryptoServiceProvider des = new DESCryptoServiceProvider();

            MemoryStream ms = new MemoryStream();

            CryptoStream cs = new CryptoStream(ms, des.CreateEncryptor(rgbKey, rgbIV), CryptoStreamMode.Write);

            using (StreamWriter sw = new StreamWriter(cs))

            {

                sw.Write(plain);

                sw.Flush();

                cs.FlushFinalBlock();

                ms.Flush();

                return Convert.ToBase64String(ms.GetBuffer(), 0, (int)ms.Length);

            }

        }

        #endregion

 

        #region DES解密字符串

        /// <summary>

        /// DES解密方法

        /// </summary>

        /// <param name="cipher">密文</param>

        /// <param name="key">密钥</param>

        /// <param name="iv">向量</param>

        /// <param name="isBase64">密文是否用base64解码</param>

        /// <returns>明文</returns>

        public static String DecryptDES(string cipher, byte[] key64, byte[] iv64)

        {

            byte[] bytesCipher;

            bytesCipher = Convert.FromBase64String(cipher);

            DESCryptoServiceProvider des = new DESCryptoServiceProvider();

            MemoryStream ms = new MemoryStream(bytesCipher);

            CryptoStream cs = new CryptoStream(ms, des.CreateDecryptor(key64, iv64), CryptoStreamMode.Read);

            using (StreamReader sr = new StreamReader(cs))

            {

                return sr.ReadToEnd();

            }

        }

        #endregion

    }