Método ConfigurationElement.IsReadOnly

// Show how to use IsReadOnly.
// It loops to see if the elements are read only. 
static void ReadOnlyElements()
{
    try
    {
        // Get the configuration file.
        System.Configuration.Configuration config =
            ConfigurationManager.OpenExeConfiguration(
            ConfigurationUserLevel.None);

        // Get the MyUrls section.
        UrlsSection myUrlsSection =
            config.GetSection("MyUrls") as UrlsSection;


        UrlsCollection elements = myUrlsSection.Urls;


        IEnumerator elemEnum =
            elements.GetEnumerator();

        int i = 0;
        Console.WriteLine(elements.Count.ToString());

        while (elemEnum.MoveNext())
        {
            Console.WriteLine("The element {0} is read only: {1}",
             elements[i].Name,
             elements[i].IsReadOnly().ToString());
            i += 1;
        }
    }
    catch (ConfigurationErrorsException err)
    {
        Console.WriteLine("[ReadOnlyElements: {0}]",
            err.ToString());
    }

}