protected void UpdateImageListing_Click(object sender, EventArgs e)
    {
        AmazonS3 util = new AmazonS3();
        Hashtable State = (Hashtable)HttpRuntime.Cache[Session.SessionID];
        ArrayList image_list = util.GetStockImageUrls(State);
        DB db = new DB();
        db.ViziAppsExecuteNonQuery(State, "DELETE FROM stock_images");

        foreach (String url in image_list)
        {
            int start = url.IndexOf("apps/images/") + 12;
            string type = url.Substring(start,url.IndexOf("/",start) - start);
            string sql = "INSERT INTO stock_images (image_url,type) VALUES ('" + url + "','" + type + "')";
            db.ViziAppsExecuteNonQuery(State, sql);

        }
        db.CloseViziAppsDatabase(State);
        Message.Text = "Image URLs have been updated in the database.";
    }