Hi,

I'm assuming you're using EPiServer 7<.

If you only need to update the list when content is published, you can listen to content repository events:

namespace DV
{
    using EPiServer;
    using EPiServer.Core;
    using EPiServer.Framework;
    using EPiServer.Framework.Initialization;
    using EPiServer.ServiceLocation;

    [InitializableModule]
    [ModuleDependency(typeof(EPiServer.Web.InitializationModule))]
    public class EventsInitialization : IInitializableModule
    {
        private bool eventsAttached;

        public void Initialize(InitializationEngine context)
        {
            if (!eventsAttached)
            {
                 var repository = ServiceLocator.Current.GetInstance<IContentEvents>();

                repository.PublishedContent += this.PublishedContent;

                eventsAttached = true;
            }
        }

        public void Preload(string[] parameters)
        {
            throw new NotImplementedException();
        }

        public void Uninitialize(InitializationEngine context)
        {
            repository.PublishedContent -= this.PublishedContent;

            eventsAttached = false;
        }

        private void PublishedContent(object sender, ContentEventArgs e)
        {
            // Do your magic here.
        }
}