Update AppSettings of config file in runtiome in asp.net Desktop Application

Update AppSettings of config file in runtime in asp.net Desktop Application 

 public static void SaveConfig(string ConSource)
        {
            string appPath = System.IO.Path.GetDirectoryName(System.Reflection.Assembly.GetExecutingAssembly().Location);
            string configFile = System.IO.Path.Combine(appPath, "b02C_core.exe.config");
            ExeConfigurationFileMap configFileMap = new ExeConfigurationFileMap();
            configFileMap.ExeConfigFilename = configFile;
            System.Configuration.Configuration config = ConfigurationManager.OpenMappedExeConfiguration(configFileMap, ConfigurationUserLevel.None);
            config.AppSettings.Settings["connectb02C_coreDB"].Value = ConSource;
            config.Save();
            ConfigurationManager.RefreshSection("connectionStrings");
        }