在几种形式之间处理应用程序设置的最佳实践是什么

Question

What is the best practice to handle application's settings contains in the external INI file between several forms?

Suppose that I have two forms -- MainForm and SettingsForm . User can open the SettingsForm from the MainForm . Now I have smth like this:

• On Load event of the SettingsForm I read application's settings from the file and change the UI appropriately
• On "Save" button press I write new options' values to the file
• On the "SettingsFormClosed" event of the MainForm I read the settings from the file again

I think that the last thing is the most terrible in this case. Maybe I should use smth like SettingsSingleton or smth like this? What is the best practice to do it in C# and Windows Forms?

Thanks in advance.

Answer 1

You should use Observer pattern . You will need a class which represents settings file, this file is Observable . Your SettingsForm and MainForm are Observers . And SettingsForm can modify the Observable .

Answer 2

I like to do it like this, make a Setting class for storing the values, then create a service class that is responsible for saving and supplying the settings to other objects. Service is implemented as a singleton and implements INotifyPropertyChanged. Then in your forms you just have to subscribe to ProperyChanging event from the service.

Example service code:

 public sealed class SettingsService : INotifyPropertyChanged
    {
        private static Lazy<SettingsService> instance = new Lazy<SettingsService>(() => new SettingsService());

        public static SettingsService Instance
        {
            get { return instance.Value; }
        }

        private Setting settings;
        public Setting Settings
        {
           get
           {
              var clone = settings.Clone();
              return clone;
           }
        }

        private SettingsService()
        {
           //load your settings
        }            

        public void SaveChanges(Setting settings)
        {
           //Do whatever you do to save the changes, and raise the event the   settings changed
           this.settings = settings;
           NotifyPropertyChanged();
        }


        private void NotifyPropertyChanged()
        {
            if (PropertyChanged != null)
               PropertyChanged(this, new PropertyChangedEventArgs("Settings"));
        }
        public event PropertyChangedEventHandler PropertyChanged;
}