C# WinForm Webbrowser 아날로그 로그인 카드

        private void Form1_Load(object sender, EventArgs e)
        {
            _strFlag = ConfigurationManager.AppSettings[_strConfigPar1] as string;
            _strNetUserName = ConfigurationManager.AppSettings[_strConfigPar2] as string;
            _strNetPassword = ConfigurationManager.AppSettings[_strConfigPar3] as string;

            if (_strNetUserName != null && _strNetPassword != null)
            {
                doDecrypt(_strNetUserName, _strNetPassword);
                webBrowser1.Navigate(_strLoginUrl);
                _blFlg = false;
            }
            else
            {
                MessageBox.Show(_strErrorMessage);
                Close();
            }
        }

        private void webBrowser1_DocumentCompleted(object sender, WebBrowserDocumentCompletedEventArgs e)
        {
            HtmlDocument doc = webBrowser1.Document;
            try
            {
                if (doc.Url.ToString() != "" && _strLoginUrl.Equals(doc.Url.ToString()))
                {
                    string strName = string.Empty;
                    string strPass = string.Empty;

                    HtmlElement heForm = doc.GetElementById("LoginForm");
                    HtmlElement heSubmit = doc.All["loginButton"];

                    strName = heForm.Children[2].GetElementsByTagName("INPUT")[0].Name;
                    strPass = heForm.Children[2].GetElementsByTagName("INPUT")[1].Name;
                    HtmlElement heUsername = doc.All[strName];
                    HtmlElement hePassword = doc.All[strPass];

                    heUsername.SetAttribute("value", _strNetUserName);
                    hePassword.SetAttribute("value", _strNetPassword);

                    heSubmit.InvokeMember("click");
                }
                else if (!_blFlg && doc.Url.ToString() != "" && _strPressUrl.Equals(doc.Url.ToString()))
                {
                    HtmlElement heLink = doc.GetElementsByTagName("A")[0];
                    heLink.InvokeMember("onclick");
                    _blFlg = true;
                }
            }
            catch
            {
                return;
            }
        }

        private static void SaveConfig(string ConnenctionString, string strKey)
        {
            XmlDocument doc = new XmlDocument();
            //          
            string strFileName = AppDomain.CurrentDomain.SetupInformation.ConfigurationFile;
            doc.Load(strFileName);
            //     “add”     
            XmlNodeList nodes = doc.GetElementsByTagName("add");
            for (int i = 0; i < nodes.Count; i++)
            {
                //        key  
                XmlAttribute att = nodes[i].Attributes["key"];
                //                         
                if (att.Value == strKey)
                {
                    //              
                    att = nodes[i].Attributes["value"];
                    att.Value = ConnenctionString;
                    break;
                }
            }
            //       
            doc.Save(strFileName);
        }