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<Fruit> <Name>Orange</Name> <Size>Large</Size> </Fruit> Press enter to finish We have created the parent XElement and added two children, and with very little effort we have a simple XML document. I have created the children and then added them to the parent, but I could have done everything in a single statement, like this: XElement myFruit = new XElement("Fruit", new XElement("Name", "Orange"), new XElement("Size", "Large")); This way of creating elements is very important when we start to use LINQ queries to generate XML in the Creating XML from LINQ Queries section later in this chapter.

In Listings 29-1 and 29-2, I created the child XElements by passing two string parameters to the constructor: the name of the element and the value. In fact, you can pass any object as the second parameter, and a string representation of the object will be included in the XML data. Listing 29-3 demonstrates this using an enum and a custom class. Listing 29-3. Using String Representations of Objects in XElements using System; using System.Xml.Linq; enum FruitSize { Small, Medium, Large } class Fruit { public Fruit(string nameParam, int stockParam) { Name = nameParam; ItemsInStock = stockParam; } public string Name { get; set; } public int ItemsInStock { get; set; } public override string ToString() { return Name; } } class Listing 03 {

static void Main(string[] args) { // create a Fruit object Fruit myFruitObject = new Fruit("Orange", 200); // create XElements using the Fruit object XElement myNameElement = new XElement("Name", myFruitObject); XElement mySizeElement = new XElement("Size", FruitSize.Large); // create a hierarchy of XElements XElement myFruitElement = new XElement("Fruit", myNameElement, mySizeElement); // print out the XElement object Console.WriteLine(myFruitElement); // wait for input before exiting Console.WriteLine("Press enter to finish"); Console.ReadLine(); } } In Listing 29-3, I pass a Fruit object as the parameter to create one XElement, which includes the result of the ToString method in the XML. The other XElement is created using a value from an enum, which is expressed as a helpful string value. Compiling and running Listing 29-3 produces the following output: <Fruit> <Name>Orange</Name> <Size>Large</Size> </Fruit> Press enter to finish Notice that only the result from the ToString method of the Fruit object is included in the XML. The Fruit class defines a property called ItemsInStock that is ignored. If you pass an object to the constructor of XElement like this, you must be sure that the ToString method returns all the information you need included in the XML. As an alternative, you can create XElements to express the value or result of individual members, as demonstrated in Listing 29-4. Listing 29-4. Creating Multiple XElements from the Members of an Object using System; using System.Xml.Linq; class Listing 04 { static void Main(string[] args) { // create a Fruit object Fruit myFruitObject = new Fruit("Orange", 200);

// create XElements using the Fruit object XElement myNameElement = new XElement("Name", myFruitObject.Name); XElement myStockElement = new XElement("ItemsInStock", myFruitObject.ItemsInStock); XElement mySizeElement = new XElement("Size", FruitSize.Large); // create a hierarchy of XElements XElement myFruitElement = new XElement("Fruit", myNameElement, myStockElement, mySizeElement); // print out the XElement object Console.WriteLine(myFruitElement); // wait for input before exiting Console.WriteLine("Press enter to finish"); Console.ReadLine(); } } Listing 29-4 explicitly creates XElements for both of the properties of the Fruit object. Compiling and running Listing 29-4 produces the following result: <Fruit> <Name>Orange</Name> <ItemsInStock>200</ItemsInStock> <Size>Large</Size> </Fruit> Press enter to finish

XElement isn t the only kind of XML node available. There are classes that you can use to create different node types. Listing 29-5 provides an example. Listing 29-5. Creating Different XML Node Types using System; using System.Xml.Linq; class Listing 05 { static void Main(string[] args) { // create an XElement XElement myElement = new XElement("ElementName", "ElementValue"); // create an attribute XAttribute myAttribute = new XAttribute("AttributeName", "AttributeValue");