Navigating the XML Document

In this post I provided a simple example of how you can programmatically create an XML Document. Once created it can be saved directly to disk by adding the following line of code to end of the function

xmlDoc.Save("cust.xml")

It is important to remember that the XMLDocument is actually an in memory DOM tree. Once the XML source is loaded in the XMLDocument object you can navigate through the DOM and manipulate the data using the .NET Framework classes. The XMLNode provides various methods that can be used to navigate through the DOM Tree. Always remember that most nodes can have multiple child nodes of various types, such as Document, Document Fragment, Entity Reference, Element and Entity. Attributes are considered a property of the element node, and consists of a name/value pair. The following table lists some of the properties of the XMlNode class that can be used to navigate through the DOM and obtain the values of the Nodes.

For example, if we had an XML file that contained the following data.

<customerList>

            <name>Major Company</name>

</customerList>

We could use the following code in a button behind a form to read the saved XML file.

Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click

        Dim xmldoc As New XmlDocument

        xmldoc.Load("cust.xml")

        Dim xmlNodes As XmlNodeList = xmldoc.DocumentElement.ChildNodes

        Dim xmlstring As New StringBuilder

        Dim custNode As XmlNode

        For Each custNode In xmlNodes

            Dim propNode As XmlNode

  For Each propnode In custNode

                xmlstring.Append(propnode.Name + ":" + propnode.InnerText)

                MsgBox(xmlstring.ToString)

            Next propNode

        Next custNode

    End Sub