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c#asp.netrsssyndication

Extract Image and More Tags from Item in RSS


I want to extract data from this URL: http://rss.cnn.com/rss/edition.rss

So each Item looks like this:

      <item>
         <title><![CDATA[Ireland stuns England at home of cricket]]></title>
         <description><![CDATA[From World Cup glory to utter humiliation in the space of 10 days.]]></description>
         <link>https://www.cnn.com/2019/07/24/sport/england-ireland-cricket-spt-intl/index.html</link>
         <guid isPermaLink="true">https://www.cnn.com/2019/07/24/sport/england-ireland-cricket-spt-intl/index.html</guid>
         <pubDate>Wed, 24 Jul 2019 13:17:56 GMT</pubDate>
         <media:group>
            <media:content medium="image" url="https://cdn.cnn.com/cnnnext/dam/assets/190724131447-england-ireland-tease-01-super-169.jpg" height="619" width="1100" />
            <media:content medium="image" url="https://cdn.cnn.com/cnnnext/dam/assets/190724131447-england-ireland-tease-01-large-11.jpg" height="300" width="300" />
            <media:content medium="image" url="https://cdn.cnn.com/cnnnext/dam/assets/190724131447-england-ireland-tease-01-vertical-large-gallery.jpg" height="552" width="414" />
            <media:content medium="image" url="https://cdn.cnn.com/cnnnext/dam/assets/190724131447-england-ireland-tease-01-video-synd-2.jpg" height="480" width="640" />
            <media:content medium="image" url="https://cdn.cnn.com/cnnnext/dam/assets/190724131447-england-ireland-tease-01-live-video.jpg" height="324" width="576" />
            <media:content medium="image" url="https://cdn.cnn.com/cnnnext/dam/assets/190724131447-england-ireland-tease-01-t1-main.jpg" height="250" width="250" />
            <media:content medium="image" url="https://cdn.cnn.com/cnnnext/dam/assets/190724131447-england-ireland-tease-01-vertical-gallery.jpg" height="360" width="270" />
            <media:content medium="image" url="https://cdn.cnn.com/cnnnext/dam/assets/190724131447-england-ireland-tease-01-story-body.jpg" height="169" width="300" />
            <media:content medium="image" url="https://cdn.cnn.com/cnnnext/dam/assets/190724131447-england-ireland-tease-01-t1-main.jpg" height="250" width="250" />
            <media:content medium="image" url="https://cdn.cnn.com/cnnnext/dam/assets/190724131447-england-ireland-tease-01-assign.jpg" height="186" width="248" />
            <media:content medium="image" url="https://cdn.cnn.com/cnnnext/dam/assets/190724131447-england-ireland-tease-01-hp-video.jpg" height="144" width="256" />
         </media:group>
      </item>

So I found some classes over the internet that should take care on situations like that, such as: SyndicationFeed or XDocument.Parse

So I tried this one out:

XmlReader reader = XmlReader.Create(urle);
            SyndicationFeed feeds = SyndicationFeed.Load(reader); // References -> Right Click -> Add Reference -> System.ServiceModel
            reader.Close();

            foreach (SyndicationItem item in feeds.Items)
            {
                string subject = item.Title.Text;
                Console.WriteLine("subject: " + subject);
                if (item.Summary != null)
                {
                    string summary = item.Summary.Text;
                    Console.WriteLine("desc: " + summary);

                }


            }

and it works pretty good with Title and Summary, but it has feature to deal with images for example, so how could i do it with SyndicationFeed for example?


Solution

  • The <media:group> and its content are considered as extension elements.

    The SyndicationFeed class has a property ElementExtensions to address these,
    with a ReadElementExtensions method to read and parse them.

    Create a class that matches the <media:group> xml element.

    [XmlRoot("group", Namespace = "http://search.yahoo.com/mrss/")]
    public class MediaGroup
    {   
        [XmlElement(ElementName = "content", Namespace = "http://search.yahoo.com/mrss/")]
        public MediaContent[] Items { get; set;}
    }
    

    Also create a class definition for the <media:content> item.

    public class MediaContent
    {
        [XmlAttribute("url")]
        public string Url {  get; set; }
    
        [XmlAttribute("height")]
        public int Height {  get; set; }
    
        [XmlAttribute("width")]
        public int Width {  get; set; }
    
        [XmlAttribute("medium")]
        public string Medium { get; set; }
    }
    

    Read and parse them using an XmlSerializer as shown below.

    var serializer = new XmlSerializer(typeof(MediaGroup));
    var mediaGroup = item.ElementExtensions
        .ReadElementExtensions<MediaGroup>("group", "http://search.yahoo.com/mrss/", serializer)
        .FirstOrDefault();
    if (mediaGroup != null)
    {
        foreach (var mediaItem in mediaGroup.Items)
        {
            Console.WriteLine(mediaItem.Url);
        }
    }
    

    Full code:

    using (var reader = XmlReader.Create(urle))
    {
        var feeds = SyndicationFeed.Load(reader);
    
        var serializer = new XmlSerializer(typeof(MediaGroup));
    
        foreach (SyndicationItem item in feeds.Items)
        {
            string subject = item.Title.Text;
            Console.WriteLine("subject: " + subject);
    
            var mediaGroup = item.ElementExtensions
                .ReadElementExtensions<MediaGroup>("group", "http://search.yahoo.com/mrss/", serializer)
                .FirstOrDefault();
            if (mediaGroup != null)
            {
                foreach (var mediaItem in mediaGroup.Items)
                {
                    Console.WriteLine(mediaItem.Url);
                }
            }                    
        }
    }