RSS

RSS or Really Simple Syndication is a format used to organise content which can then be published or sent to different data consumers. For simplicity we will assume our content to be an article. When converting our article into RSS 2.0 format (which is what we will focus on) we have to create an XML file (XML version 1.0) and add certain elements to it. Once this is done, our document is ready.

There are two main components of an RSS file, the channel and item. To understand these components we have to consider an example of a newspaper. It has several articles, some grouped under the sports section, some grouped under finance section and so on.

The RSS feed which publishes these news articles will have a channel named sports and each sport article will be an item under this channel and we will have a similar channel for finance and all other sections.

With this scenario in mind, lets create our very own RSS feed to publish articles. In the example below we will be publishing two articles under the sports section and one under finance by a magazine called Magazine100. This is how our overall RSS feed would look like:

<rss version="2.0">

<channel>                         

<title>Sports</title>

<link>http://www.magazine100.com/sports</link>

<description>Sports news by magazine100</description>

<item>                

<title>cricket updates</title>

<description>Here you can paste the entire article</description>                           

</item>

<item>                

<title>football updates</title>

<description>Here you can paste the entire article</description>                           

</item>              

</channel>

<channel>         

<title>Finance</title>

<link>http://www.magazine100.com/finance</link>

<description>Finance news by magazine100</description>

               

<item>                

<title>wall street updates</title>

<description>Here you can paste the entire article</description>                           

</item>

</channel>

</rss>

As you can see at the top level we have <rss version="2.0">. This is a mandatory attribute that specifies the version that this document conforms to.

We then have a channel which is described by the tags <title>, <link> and <description>. These tags are mandatory for each channel, however if we feel the need to describe our channel further, there are several additional tags that we can use. You can get a list of these tags from here.

After channel, we have an item tag which uses <title> and <description> to publish the content of an article. For an item, it is mandatory to have at least one of these two fields (title and description), and similar to a channel, an item can also be further described using optional tags. You can get a list of these tags from here.

The problem with an item is that you do not have a tag to attach pictures. However this can be done if we use the following html within the content of the "description" tag:

<img src="[location of image]" alt="[alternate text]" title="[title of image]" />.

This code will place the image within the content of our article and solve our biggest headache (at least for me it was).

CSS for beginners

If we want to style any control in an html page (by control I mean textboxes, labels and all other html elements that can be displayed in an html page), we can easily do it using the style property. For example if we have the following heading:

<h2> Heading </h2>

And we wish to change its colour to green and make it italic, we can easily do so using the style property as shown below:

<h2 style="color: green; font-style: italic;"> Heading </h2>

Similarly, we can use a range of properties to stylize any control we want. However, this is not a very good programming practise. If we want to stylise our controls in a way that makes our styles more re-useable, we need to do it in the following way:

On top of the page we need to write the following code to make a style class with any name we want (in this example I have used the name MyHeading).

<style>

        .MyHeading

        {

            color: Green;  

            font-style: italic;

        }

</style>

Then in our html we can write the following code:

<h2 class="MyHeading"> Heading </h2>

With this code we will be achieving exactly the same result as above with the added benefit of code re-use in other places such as:

<p class="Myheading">This is a paragraph</p>

In this approach, we are using a style class to style our page. This can be a good approach to style a page; however we can go one step further by using a cascading style sheet.

Cascading style sheets (or CSS) allow us to create a “.css” file containing many style classes. This css file can then be attached with any webpage giving it access to all its style classes.

 To attach a css file to an html page, we need to write the following line on top of the webpage (above its html code):

<link rel="Stylesheet" type="text/css" href="/Location/File.css" />

In the css file, we need to write the following code to create a style class:

.MyHeading

{

      color: Green;  

      font-style: italic;

}

After this, we can use any class from the css file to style the controls of our page. The benefit of using this approach is that css files allow us to use the same style sheet throughout our website, and ensure a consistent layout across all pages, thus allowing maximum code re-use.

Returning XML from MVC Controller Action

To return xml from a mvc controller action we can use the following code:

public XmlElement name_of_function()
{
      XmlDocument Feed = new XmlDocument();
      XmlWriter Write = Feed.CreateNavigator().AppendChild();

      Write.WriteStartDocument();
      Write.WriteStartElement("head");
      Write.WriteElementString("name_of_tag", "value");
      Write.WriteEndElement();
      Write.WriteEndDocument();

      Write.Flush();
      Write.Close()

      return Feed.DocumentElement;
}