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);
}