XElement highriseRoot = XElement.Load("highrise-contact.xml");

We use the static Load method of XElement to load the XML contained within the "highrise-contact.xml" file that we've saved locally. I don't believe the Highrise API is officially supported at the moment so I'm not going to load the contact details directly from the highrisehq.com site. Perhaps, in a future post we can explore that as an option.

Anywho, once our XML is loaded into an XElement, we can transform our Highrise XML into the hCard microformat by building a new XElement. We'll use the Element query axis method to retrieve the first and last name of the contact, and we'll embed query expressions and make use of the Descendants query axis method for selecting all the email and web addresses for the contact within the source XML. When we put it all together we end up with the C# code below:

XElement highriseRoot = XElement.Load("highrise-contact.xml");

XElement hCard =
    new XElement("div",
        new XAttribute("class", "vcard"),
        new XElement("div",
            new XAttribute("class", "fn"),
            highriseRoot.Element("first-name") + " " + highriseRoot.Element("last-name")
        ),
        from emailElement in highriseRoot.Descendants("email-address")
        select new XElement("div",
            "Email:",
            new XElement("span",
                new XAttribute("class", "email"),
                (string) emailElement.Element("address")
            )
        ),
        from webElement in highriseRoot.Descendants("web-address")
        select
        new XElement("a",
            new XAttribute("class", "url"),
            new XAttribute("href", (string) webElement.Element("url")),
            (string) webElement.Element("url")
        )
    );

Console.WriteLine(hCard);

At first glance, the above code might be overwhelming. However, once you come to understand the power of functional construction you'll quickly realize how wonderful LINQ to XML can be for transforming XML to alternate XML formats. In addition to making it easy to transform XML into alternate XML formats, LINQ to XML also makes it very easy to transform XML into objects. If we have a Contact class defined as:

public class Contact {
    public string Name { get; set; }
    public IEnumerable<string> EmailAddresses { get; set; }
    public IEnumerable<string> Urls { get; set; }
}

We can transform the contact details in our XML into a Contact instance with the following code:

Contact contact = new Contact {
    Name = (string) highriseRoot.Element("first-name") + " " + (string) highriseRoot.Element("last-name"),
    EmailAddresses = highriseRoot.Descendants("email-address").Select(e => (string)e.Element("address")),
    Urls = highriseRoot.Descendants("web-address").Select(e => (string)e.Element("url"))
};

After looking back at the sample here I wish I had chosen an XML fragment with a little more hierarchy, however it's much too late for that now. Hopefully, the code included in this post gives you a small taste of the types of XML transformations possible with LINQ to XML. As you begin to work with LINQ to XML, you'll find that functional construction, combined with query axis methods, and query expressions provide a tremendous amount of flexibility for transforming XML. Additionally, the new object initializer syntax and LINQ to XML's ability to easily construct objects from XML makes it very easy to create objects from XML. I've attached a zip file with the code above to this post. (VS2008 Beta 2 Required) LINQtoXMLTransformSample.zip (23.69 KB)

• Find someplace quite to work.  Unlike programming (and other tasks) where a little bit of background noise and/or music can be beneficial, writing needs quite and needs thought.  Find someplace you can think.  Don't try and get a little bit of writing done while you try and do something else (such as watch after the kiddos).
• Start with an outline of what your going to write.  Include the key goals that you have for each section and make sure you address each goal before you finish the section, or chapter.
• With your first draft don't worry about how terrible things sounds, how rough around the edges your points and/or description are, and how utterly crappy things flow.  Get your thoughts on paper.  Once you get everything out, go back and revise mercilessly until things sounds the way you want.
• Always think about the reader.  How will they expect to consume the information you're presenting?  What will they arleady know? What might they need to be reminded of?  How can you leverage what they know to help them learn what you're writing about?
• Don't be boring.  This might sounds obvious but I've found it very hard to present everything you want the reader to learn without having things turn into an unending flow of technical details, which results in boredom.  It's important to remember the reader needs breaks, encouragement, and direction.  And they also need to not be bored.
• Instead of writing blog posts about how hard writing is and then spewing off a bunch of writing tips (as if you have any clue what you're talking about) stay focused on your book and the deadlines you have....doh! :)