This post originated from an RSS feed registered with .NET Buzz by -. Original Post: Beispiel für LINQ to Objects und Extension Methods Feed Title: Norbert Eder - Living .NET Feed URL: http://feeds.feedburner.com/NorbertEder-Livingnet Feed Description: Copyright (c)2005, 2006 by Norbert Eder Latest .NET Buzz Posts Latest .NET Buzz Posts by - Latest Posts From Norbert Eder - Living .NET

public class Person
{
    public int Id { get; set; }
    public string Firstname { get; set; }
    public string Lastname { get; set; }
}

static class PersonListExtension
{
    public static XmlDocument ToXml(this List<Person> personList)
    {
        XmlDocument doc = new XmlDocument();
        XmlNode xnRoot = doc.CreateElement("PersonList");
        doc.AppendChild(xnRoot);

        foreach (Person p in personList)
        {
            XmlNode xnPerson = doc.CreateElement("Person");
            XmlNode xnId = doc.CreateElement("Id");
            XmlNode xnFirstname = doc.CreateElement("Firstname");
            XmlNode xnLastname = doc.CreateElement("Lastname");

            xnId.InnerText = p.Id.ToString();
            xnFirstname.InnerText = p.Firstname;
            xnLastname.InnerText = p.Lastname;

            xnPerson.AppendChild(xnId);
            xnPerson.AppendChild(xnFirstname);
            xnPerson.AppendChild(xnLastname);

            xnRoot.AppendChild(xnPerson);
        }
        return doc;
    }
}

List<Person> personList = new List<Person>();

for (int i = 0; i < 10; i++)
{
    Person p = new Person() 
    { Id = i, Firstname = "Norbert", Lastname = "Eder" };
    personList.Add(p);
}

var pList = from p in personList
            where p.Id < 5
            select p.Id + " " + p.Lastname + " " + p.Firstname;

Console.WriteLine("---PERSONLIST-XML---");
Console.WriteLine(personList.ToXml().OuterXml);
Console.WriteLine("---QUERY-RESULT---");
foreach (string s in pList)
    Console.WriteLine(s);