XPathNavigator.Evaluate (XPathExpression)
Imports System
Imports System.Xml
Imports System.Xml.XPath
Public Class MainClass
Public Shared Sub Main()
Dim document As XPathDocument = New XPathDocument("books.xml")
Dim navigator As XPathNavigator = document.CreateNavigator()
Dim query As XPathExpression = navigator.Compile("sum(descendant::book/price)")
Dim total As Double = CType(navigator.Evaluate(query), Double)
Console.WriteLine("Total price for all books: {0}", total.ToString())
End Sub
End Class