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        private string AppConfigRead(string keyName)

        {

            string strReturn;

            Configuration currentConfig =

                ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None);

            if (currentConfig.AppSettings.Settings.AllKeys.Contains(keyName))

                strReturn = currentConfig.AppSettings.Settings[keyName].Value;

            else

                strReturn = ""; //키가없으면.

            return strReturn;

        }

        private bool AppConfigWrite(string keyName, string value)

        {

            Configuration currentConfig =

                ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None);

            if (currentConfig.AppSettings.Settings.AllKeys.Contains(keyName)) //키가 있으면

                currentConfig.AppSettings.Settings[keyName].Value = value;

            else       //키가 없으면

                currentConfig.AppSettings.Settings.Add(keyName, value);

            currentConfig.Save();

            ConfigurationManager.RefreshSection("appSettings");   // 내용 갱신             

            return true;

        }