AGGREGER PLUSIEURS FLUX RSS DANS UN GRIDVIEW

public partial class Aggregation : Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        //configuration
        Dictionary<string, string> bloggers = new Dictionary<string, string>();

        bloggers.Add("Florent Santin", "http://blogs.developpeur.org/azra/rss.aspx");
        bloggers.Add("Christian Robert", "http://blogs.developpeur.org/christian/rss.aspx");
        bloggers.Add("Nixounet", "http://blogs.developpeur.org/nix");
        bloggers.Add("JavaScript warrior", "http://blogs.developpeur.org/cyril");

        int NbMessageAffiche = 10;


        List<BlogMessage> elem;

        //gestion du cache
        if (Cache["LastData"] == null)
        {
        //algo, on va creer la liste
        elem = new List<BlogMessage>();

        //récupération des derniers messages
        foreach (KeyValuePair<string, string> pair in bloggers)
        {
            GenericRssChannel c = GenericRssChannel.LoadChannel(pair.Value);
        
            IEnumerator Ienum = c.Items.GetEnumerator();
            while (Ienum.MoveNext())
            {
                GenericRssElement curr = (GenericRssElement)Ienum.Current;
                elem.Add(
                    new BlogMessage(pair.Key, curr.Attributes["title"], curr.Attributes["link"],
                                    DateTime.Parse(curr.Attributes["pubDate"])));
            }
        }
         elem.Sort();
            
         //mise en cache de liste pour une heure
          Cache.Insert("LastData", elem, null, Cache.NoAbsoluteExpiration, new TimeSpan(1, 0, 0),
                         CacheItemPriority.Default, null);
        }
        else
        {
            //l object est deja en cache, on le récupére
            elem = Cache["LastData"] as List<BlogMessage>;
        }

        GridView1.DataSource = elem.GetRange(0, NbMessageAffiche);
        GridView1.DataBind();
    }
}

public class BlogMessage : IComparable<BlogMessage>
{
    private string _nom;

    public string Nom
    {
        get { return _nom; }
        set { _nom = value; }
    }

    private string _title;

    public string Title
    {
        get { return _title; }
        set { _title = value; }
    }

    private DateTime _pubdate;

    public DateTime PubDate
    {
        get { return _pubdate; }
        set { _pubdate = value; }
    }

    private string _link;

    public string Link
    {
        get { return _link; }
        set { _link = value; }
    }

    public BlogMessage(string nom, string title, string link, DateTime pubdate)
    {
        _nom = nom;
        _title = title;
        _link = link;
        _pubdate = pubdate;
    }

    #region IComparable<BlogMessage> Members

    public int CompareTo(BlogMessage other)
    {
        if (this.PubDate > other.PubDate)
            return -1;
        else if (this.PubDate < other.PubDate)
            return 1;
        else
            return 0;
    }

    #endregion
}