private static RssItem SelectNewvestRssRssItem(RssFeed feed, DateTime buildDate)
 {
     return feed.Channels.OfType<RssChannel>()
                .SelectMany(chanel => chanel.Items.OfType<RssItem>())
                .Where(item => IsNewerThanCurrent(item, buildDate))
                .OrderByDescending(selected => selected.PubDate)
                .FirstOrDefault();
 }
 /// <summary>Reads the specified RSS feed</summary>
 /// <param name="Request">The specified way to connect to the web server</param>
 /// <param name="oldFeed">The cached version of the feed</param>
 /// <returns>The current contents of the feed</returns>
 /// <remarks>Will not download the feed if it has not been modified</remarks>
 public static RssFeed Read(HttpWebRequest Request, RssFeed oldFeed)
 {
     return read(oldFeed.url, Request, oldFeed);
 }
        private static RssFeed read(string url, HttpWebRequest request, RssFeed oldFeed)
        {
            // ***** Marked for substantial improvement
            RssFeed feed = new RssFeed();
            RssElement element = null;
            Stream stream = null;
            Uri uri = new Uri(url);
            feed.url = url;

            switch (uri.Scheme)
            {
                case "file":
                    feed.lastModified = File.GetLastWriteTime(url);
                    if ((oldFeed != null) && (feed.LastModified == oldFeed.LastModified))
                    {
                        oldFeed.cached = true;
                        return oldFeed;
                    }
                    stream = new FileStream(url, FileMode.Open, FileAccess.Read, FileShare.ReadWrite);
                    break;
                case "https":
                    goto case "http";
                case "http":
                    if (request == null)
                        request = (HttpWebRequest)WebRequest.Create(uri);
                    if (oldFeed != null)
                    {
                        request.IfModifiedSince = oldFeed.LastModified;
                        request.Headers.Add("If-None-Match", oldFeed.ETag);
                    }
                    try
                    {
                        HttpWebResponse response = (HttpWebResponse)request.GetResponse();
                        feed.lastModified = response.LastModified;
                        feed.etag = response.Headers["ETag"];
                        try
                        {
                            if (response.ContentEncoding != "")
                                feed.encoding = Encoding.GetEncoding(response.ContentEncoding);
                        }
                        catch {}
                        stream = response.GetResponseStream();
                    }
                    catch (WebException we)
                    {
                        if (oldFeed != null)
                        {
                            oldFeed.cached = true;
                            return oldFeed;
                        }
                        else throw we; // bad
                    }
                    break;
            }

            if (stream != null)
            {
                RssReader reader = null;
                try
                {
                    reader = new RssReader(stream);
                    do
                    {
                        element = reader.Read();
                        if (element is RssChannel)
                            feed.Channels.Add((RssChannel)element);
                    }
                    while (element != null);
                    feed.rssVersion = reader.Version;
                }
                finally
                {
                    feed.exceptions = reader.Exceptions;
                    reader.Close();
                }
            }
            else
                throw new ApplicationException("Not a valid Url");

            return feed;
        }
 /// <summary>Determines whether the RssFeedCollection contains a specific element.</summary>
 /// <param name="rssFeed">The RssFeed to locate in the RssFeedCollection.</param>
 /// <returns>true if the RssFeedCollection contains the specified value; otherwise, false.</returns>
 public bool Contains(RssFeed rssFeed)
 {
     return List.Contains(rssFeed);
 }
 /// <summary>Reads the specified RSS feed</summary>
 /// <param name="oldFeed">The cached version of the feed</param>
 /// <returns>The current contents of the feed</returns>
 /// <remarks>Will not download the feed if it has not been modified</remarks>
 public static RssFeed Read(RssFeed oldFeed)
 {
     return read(oldFeed.url, null, oldFeed);
 }
 /// <summary>Adds a specified feed to this collection.</summary>
 /// <param name="feed">The feed to add.</param>
 /// <returns>The zero-based index of the added feed.</returns>
 public int Add(RssFeed feed)
 {
     return List.Add(feed);
 }
 /// <summary>Removes a specified category from this collection.</summary>
 /// <param name="feed">The category to remove.</param>
 public void Remove(RssFeed feed)
 {
     List.Remove(feed);
 }
 /// <summary>Inserts a feed into this collection at a specified index.</summary>
 /// <param name="index">The zero-based index of the collection at which to insert the feed.</param>
 /// <param name="feed">The feed to insert into this collection.</param>
 public void Insert(int index, RssFeed feed)
 {
     List.Insert(index, feed);
 }
 /// <summary>Searches for the specified RssFeed and returns the zero-based index of the first occurrence within the entire RssFeedCollection.</summary>
 /// <param name="rssFeed">The RssFeed to locate in the RssFeedCollection.</param>
 /// <returns>The zero-based index of the first occurrence of RssFeed within the entire RssFeedCollection, if found; otherwise, -1.</returns>
 public int IndexOf(RssFeed rssFeed)
 {
     return List.IndexOf(rssFeed);
 }
 /// <summary>Copies the entire RssFeedCollection to a compatible one-dimensional <see cref="Array"/>, starting at the specified index of the target array.</summary>
 /// <param name="array">The one-dimensional RssFeed Array that is the destination of the elements copied from RssFeedCollection. The Array must have zero-based indexing.</param>
 /// <param name="index">The zero-based index in array at which copying begins.</param>
 /// <exception cref="ArgumentNullException">array is a null reference (Nothing in Visual Basic).</exception>
 /// <exception cref="ArgumentOutOfRangeException">index is less than zero.</exception>
 /// <exception cref="ArgumentException">array is multidimensional. -or- index is equal to or greater than the length of array.-or-The number of elements in the source RssFeedCollection is greater than the available space from index to the end of the destination array.</exception>
 public void CopyTo(RssFeed[] array, int index)
 {
     List.CopyTo(array, index);
 }