update app.config file programmatically with ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None);

Question

update app.config file programmatically with

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

Answer 1

You can use the following code:

private void UpdateConfig(string key, string value, string fileName)
{
    var configFile = ConfigurationManager.OpenExeConfiguration(fileName);
    configFile.AppSettings.Settings[key].Value = value;

    configFile.Save();
}

Where: fileName is the full path + application name (c:\project\application.exe)

In your case, change the AppSetting by Sections:

configFile.Sections["nhibernateSettings"]