public static void SaveAppSetting(string configurationName, AppSetting setting)
 {
     lock (LockObject)
     {
         var configuration = LoadConfiguration(Settings.SettingsFilePath);
         var config = configuration[configurationName];
         config.AddAppSetting(setting);
         SaveConfigurationInternal(configuration, Settings.SettingsFilePath);
     }
 }
 public void AddAppSetting(AppSetting setting)
 {
     if (string.IsNullOrWhiteSpace(setting.Name)) throw new ArgumentNullException("Name must be specified.");
     AppSetting newSetting = GetAppSetting(setting.Name);
     if (newSetting == null)
     {
         newSetting = setting;
         _appSettings.Add(newSetting);
     }
     else
         newSetting.Value = setting.Value;
 }