C# 4 and .NET 4

Using XPathnavigators ❘ 921
This time, you see the total cost of the books evaluated in the text
box (see Figure 33-3).
Now let’s say that you need to add a node for discount. You can
use the InsertAfter method to get this done fairly easily. Here is
the code:
private void button3_Click(object sender, EventArgs e)
{
XmlDocument doc = new XmlDocument();
doc.Load("books.xml");
XPathNavigator nav = doc.CreateNavigator();
if (nav.CanEdit)
{
XPathNodeIterator iter =
nav.Select("/bookstore/book/price");
while (iter.MoveNext())
{
iter.Current.InsertAfter("5");
}
}
doc.Save("newbooks.xml");
}
figure 33-3
code snippet frmNavigator.cs
Here, you add the 5 element after the price elements. First, all of the price nodes are
selected. The XPathNodeIterator is used to iterate over the nodes, and the new node is inserted. The
modified document is saved with a new name, newbooks.xml. The new version looks like the following:
The Autobiography of Benjamin Franklin
Benjamin
Franklin
8.99
5
The Confidence Man
Herman
Melville
11.99
5
The Gorgias
Plato
9.99
5
www.it-ebooks.info