DES加解密、MD5加密

        /// <summary>
        /// DES加密
        /// </summary>
        /// <param name="key">密钥</param>
        /// <param name="IV">向量（可以和密钥相同，解密需要）</param>
        /// <param name="content">要加密的内容</param>
        /// <returns>密文</returns>
        public static string Encrypt_DES(string key, string IV, string content)
        {
            if (!string.IsNullOrEmpty(key) && !string.IsNullOrEmpty(IV) && !string.IsNullOrEmpty(content))
            {
                byte[] bKey = Encoding.UTF8.GetBytes(key);
                byte[] bIV = Encoding.UTF8.GetBytes(IV);
                byte[] byteArray = Encoding.UTF8.GetBytes(content);

                string encrypt = null;
                DESCryptoServiceProvider des = new DESCryptoServiceProvider();
                try
                {
                    using (MemoryStream mStream = new MemoryStream())
                    {
                        using (CryptoStream cStream = new CryptoStream(mStream, des.CreateEncryptor(bKey, bIV), CryptoStreamMode.Write))
                        {
                            cStream.Write(byteArray, 0, byteArray.Length);
                            cStream.FlushFinalBlock();
                            encrypt = Convert.ToBase64String(mStream.ToArray());
                            cStream.Close();
                            cStream.Dispose();
                        }
                        mStream.Close();
                        mStream.Dispose();
                    }
                }
                catch (Exception err) { }
                des.Clear();

                return encrypt;
            }
            return null;
        }


        /// <summary>
        /// DES解密
        /// </summary>
        /// <param name="key">密钥</param>
        /// <param name="IV">向量</param>
        /// <param name="encryptStr">需要解密的字符串</param>
        /// <returns>原文</returns>
        public static string Decrypt_DES(string key, string IV, string encryptStr)
        {
            if (!string.IsNullOrEmpty(key) && !string.IsNullOrEmpty(IV) && !string.IsNullOrEmpty(encryptStr))
            {
                string decrypt = null;
                DESCryptoServiceProvider des = new DESCryptoServiceProvider();
                try
                {
                    byte[] bKey = Encoding.UTF8.GetBytes(key);
                    byte[] bIV = Encoding.UTF8.GetBytes(IV);
                    byte[] byteArray = Convert.FromBase64String(encryptStr);
                    using (MemoryStream mStream = new MemoryStream())
                    {
                        using (CryptoStream cStream = new CryptoStream(mStream, des.CreateDecryptor(bKey, bIV), CryptoStreamMode.Write))
                        {
                            cStream.Write(byteArray, 0, byteArray.Length);
                            cStream.FlushFinalBlock();
                            decrypt = Encoding.UTF8.GetString(mStream.ToArray());
                        }
                    }
                }
                catch (Exception err) { }
                des.Clear();

                return decrypt;
            }
            return null;
        }


        /// <summary>
        /// MD5加密
        /// </summary>
        /// <param name="text">要加密的字符串或参数名称</param>
        /// <param name="charset">字符串编码格式,一般填utf-8</param>
        /// <param name="isArg">加密字符串类型 true:参数值 false:字符串,一般选false</param>
        /// <returns></returns>
        public static string MD5(string text, string charset, bool isArg)
        {
            try
            {
                MD5CryptoServiceProvider MD5 = new MD5CryptoServiceProvider();

                if (isArg)
                {
                    NameValueCollection Collect = HttpUtility.ParseQueryString(HttpContext.Current.Request.Url.Query, Encoding.GetEncoding(charset));
                    //使用Collect接收参数值
                    if (Collect[text] != null)
                    {
                        return BitConverter.ToString(MD5.ComputeHash(Encoding.GetEncoding(charset).GetBytes(Collect[text].ToString()))).Replace("-", "");
                    }
                }
                else
                {
                    return BitConverter.ToString(MD5.ComputeHash(Encoding.GetEncoding(charset).GetBytes(text))).Replace("-", "");
                }
            }
            catch (Exception err)
            {
                
            }
            return string.Empty;
        }