aggregator

Displaying the News Items for a Particular Syndication Feed The next task that faces us is creating the DisplayNewsItems.aspx Web page. This page should display the titles of the news items in the selected syndication feed as hyperlinks such that when the hyperlink is clicked the description of the news item is shown in the bottom right frame. This task presents us with two primary challenges:

With the rise of always-on Internet connections in homes and businesses, and the continued explosive growth of the World Wide Web and Internet-accessible applications, it is becoming more and more important for applications to be able to share data with each other. Sharing data among disparate platforms requires a platform-neutral data format that can be easily transmitted via standard Internet protocols-this is where XML fits in. Since XML files are essentially, simple text files with well-known encodings, and since there exist XML parsers for all commonly used programming languages, XML data can be easily consumed by any platform.

Consuming a Syndication Feed in an ASP.NET Web Page In order to test the syndication engine we just created, let's build an online news aggregator that allows for any number of syndication feeds. The aggregator user interface will be fairly straightforward, comprising of three frames, as shown in Figure 2. In the left frame, a list of the various syndication feeds will be listed. In the top right frame, the news items for the selected syndication feed will be displayed. Finally, in the bottom right frame, the title and description of the selected news item feed will be displayed, with a link to the news item. Note that this UI is pretty much the de facto standard UI for aggregators of all kinds, including news aggregators, email clients and newsgroup readers.

Creating the Syndication Output via an ASP.NET Web Page Now that we've seen how our news items are stored along with the RSS 2.0 specification, we're ready to create an ASP.NET Web page that, when requested, will return our Web site's syndicated content. More specifically, we'll create an ASP.NET Web page named rss.aspx that will return the five most recent news items from the Articles database table, formatted according to the RSS 2.0 specification.