DES加密解密 MD5加密解密

 #region  MD5 加密

        /// <summary>
        /// MD5加密静态方法
        /// </summary>
        /// <param name="EncryptString">待加密的密文</param>
        /// <returns></returns>
        public static string MD5Encrypt(string EncryptString)
        {
            if (string.IsNullOrEmpty(EncryptString))
            {
                throw (new Exception("密文不得为空"));
            }

            MD5 m_ClassMD5 = new MD5CryptoServiceProvider();
            string m_strEncrypt = "";
            try
            {
                m_strEncrypt = BitConverter.ToString(m_ClassMD5.ComputeHash(Encoding.Default.GetBytes(EncryptString))).Replace("-", "");
            }
            catch (ArgumentException ex) { throw ex; }
            catch (CryptographicException ex) { throw ex; }
            catch (Exception ex) { throw ex; }
            finally {
                m_ClassMD5.Clear();
            }

            return m_strEncrypt;
        }

        #endregion

        #region  DES 加密解密  可以自己设定
        private static string DesKey = "wanwanzz";

        /// <summary>
        /// DES 加密（数据加密标准，速度较快，适用于加密大量数据的场合）
        /// </summary>
        /// <param name="EncryptString">待加密的密文</param>
        /// <returns></returns>
        public static string DESEncrypt(string EncryptString)
        {
            if (string.IsNullOrEmpty(EncryptString))
            {
                throw (new Exception("密文不得为空"));
            }
            if (string.IsNullOrEmpty(DesKey))
            {
                throw (new Exception("密钥不得为空"));
            }
            if (DesKey.Length!=8)
            {
                throw (new Exception("密钥必须为8位"));
            }

            //定义偏移量
            byte[] m_btIV = { 0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF };

            string m_strEncrypt = "";

            DESCryptoServiceProvider m_DESProvider = new DESCryptoServiceProvider();
            try
            {
                byte[] m_btEncryptString = Encoding.Default.GetBytes(EncryptString);
                MemoryStream m_stream = new MemoryStream();
                CryptoStream m_cstream = new CryptoStream(m_stream, m_DESProvider.CreateEncryptor(Encoding.Default.GetBytes(DesKey), m_btIV), CryptoStreamMode.Write);
                m_cstream.Write(m_btEncryptString, 0, m_btEncryptString.Length);
                m_cstream.FlushFinalBlock();
                m_strEncrypt = Convert.ToBase64String(m_stream.ToArray());
                m_stream.Close();
                m_stream.Dispose();
                m_cstream.Close();
                m_cstream.Dispose();

            }
            catch (IOException ex) { throw ex; }
            catch (CryptographicException ex) { throw ex; }
            catch (ArgumentException ex) { throw ex; }
            catch (Exception ex) { throw ex; }

            finally
            {
                m_DESProvider.Clear();
            }
            return m_strEncrypt;
        }

        /// <summary>
        /// DES 解密(数据加密标准，速度较快，适用于加密大量数据的场合)
        /// </summary>
        /// <param name="DecryptString"></param>
        /// <returns></returns>
        public static string DESDecrypt(string DecryptString)
        {
            if (string.IsNullOrEmpty(DecryptString))
            {
                throw (new Exception("密文不得为空"));
            }
            if (string.IsNullOrEmpty(DesKey))
            {
                throw (new Exception("密钥不得为空"));
            }
            if (DesKey.Length != 8)
            {
                throw (new Exception("密钥必须为9位"));
            }

            byte[] m_btIV = { 0x12,0x34,0x56,0x78,0x90,0xAB,0xCD,0xEF};
            string m_strDecrpty = "";
            DESCryptoServiceProvider m_DESProvider = new DESCryptoServiceProvider();
            try
            {
                byte[] m_btDecrptyString = Convert.FromBase64String(DecryptString);
                MemoryStream m_stream = new MemoryStream();
                CryptoStream m_cstream = new CryptoStream(m_stream, m_DESProvider.CreateDecryptor(Encoding.Default.GetBytes(DesKey), m_btIV), CryptoStreamMode.Write);
                m_cstream.Write(m_btDecrptyString, 0, m_btDecrptyString.Length);
                m_cstream.FlushFinalBlock();
                m_strDecrpty = Encoding.Default.GetString(m_stream.ToArray());
                m_stream.Close();
                m_stream.Dispose();
                m_cstream.Close();
                m_cstream.Dispose();
            }
            catch (IOException ex) { throw ex; }
            catch (CryptographicException ex) { throw ex; }
            catch (ArgumentException ex) { throw ex; }
            catch (Exception ex) { throw ex; }

            return m_strDecrpty;
        }

        #endregion

        #region MD5加密解密
        /// <summary>
        /// MD5加密
        /// </summary>
        /// <param name="strSource">需要加密的字符串</param>
        /// <returns>MD5加密后的字符串</returns>
        public static string Md5Encrypt(string strSource)
        {
            //把字符串放到byte数组中
            byte[] bytIn = System.Text.Encoding.Default.GetBytes(strSource);
            //建立加密对象的密钥和偏移量
            byte[] iv = { 102, 16, 93, 156, 78, 4, 218, 32 };//定义偏移量
            byte[] key = { 55, 103, 246, 79, 36, 99, 167, 3 };//定义密钥
            //实例DES加密类
            DESCryptoServiceProvider mobjCryptoService = new DESCryptoServiceProvider();
            mobjCryptoService.Key = iv;
            mobjCryptoService.IV = key;
            ICryptoTransform encrypto = mobjCryptoService.CreateEncryptor();
            //实例MemoryStream流加密密文件
            System.IO.MemoryStream ms = new System.IO.MemoryStream();
            CryptoStream cs = new CryptoStream(ms, encrypto, CryptoStreamMode.Write);
            cs.Write(bytIn, 0, bytIn.Length);
            cs.FlushFinalBlock();
            return System.Convert.ToBase64String(ms.ToArray());
        }
        #endregion

        #region MD5解密
        /// <summary>
        /// MD5解密
        /// </summary>
        /// <param name="Source">需要解密的字符串</param>
        /// <returns>MD5解密后的字符串</returns>
        public static string Md5Decrypt(string Source)
        {
            //将解密字符串转换成字节数组
            byte[] bytIn = System.Convert.FromBase64String(Source);
            //给出解密的密钥和偏移量，密钥和偏移量必须与加密时的密钥和偏移量相同
            byte[] iv = { 102, 16, 93, 156, 78, 4, 218, 32 };//定义偏移量
            byte[] key = { 55, 103, 246, 79, 36, 99, 167, 3 };//定义密钥
            DESCryptoServiceProvider mobjCryptoService = new DESCryptoServiceProvider();
            mobjCryptoService.Key = iv;
            mobjCryptoService.IV = key;
            //实例流进行解密
            System.IO.MemoryStream ms = new System.IO.MemoryStream(bytIn, 0, bytIn.Length);
            ICryptoTransform encrypto = mobjCryptoService.CreateDecryptor();
            CryptoStream cs = new CryptoStream(ms, encrypto, CryptoStreamMode.Read);
            StreamReader strd = new StreamReader(cs, Encoding.Default);
            return strd.ReadToEnd();
        }
        #endregion