ConfigurationManager.AppSettings - How to modify and save?

Question

It might sound too trival to ask and I do the same thing as suggested in articles, yet it doesn't work as expected. Hope someone can point me to the right direction.

I would like to save the usersettings per AppSettings.

Once the Winform is closed I trigger this:

conf.Configuration config = 
           ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None);

if (ConfigurationManager.AppSettings["IntegrateWithPerforce"] != null)
    ConfigurationManager.AppSettings["IntegrateWithPerforce"] = 
                                           e.Payload.IntegrateCheckBox.ToString();
else
    config.AppSettings.Settings.Add("IntegrateWithPerforce", 
                                          e.Payload.IntegrateCheckBox.ToString());

config.Save(ConfigurationSaveMode.Modified);

So the first time when the entry doesnt exist yet, it would simply create it, otherwise it would modify the existing entry. However this doesn't save.

1) What am I doing wrong?

2) Where am I expecting the usersettings for App settings to be saved again? Is it in the Debug folder or in C:\Documents and Settings\USERNAME\Local Settings\Application Data folder?

Answer 1

I know I'm late :) But this how i do it:

public static void AddOrUpdateAppSettings(string key, string value)
{
    try
    {
        var configFile = ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None);
        var settings = configFile.AppSettings.Settings;
        if (settings[key] == null)
        {
            settings.Add(key, value);
        }
        else
        {
            settings[key].Value = value;
        }
        configFile.Save(ConfigurationSaveMode.Modified);
        ConfigurationManager.RefreshSection(configFile.AppSettings.SectionInformation.Name);
    }
    catch (ConfigurationErrorsException)
    {
        Console.WriteLine("Error writing app settings");
    }
}

For more information look at MSDN