Private Sub removeComment(ByVal parent As XmlNode) Dim node As XmlNode = parent.FirstChild Do If node Is Nothing Then Exit Do Dim nextNode As XmlNode = node.NextSibling If node.NodeType = XmlNodeType.Comment Then parent.RemoveChild(node) Else removeComment(node) End If node = nextNode Loop End Sub Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load Const xmlns As String = "http://www.atmarkit.co.jp/xmlns/sample/person" Dim document As New XmlDocument() document.Load("c:\sample.xml") removeComment(document) Dim ageList As XmlNodeList = document.GetElementsByTagName("age", xmlns) Dim ageNode As XmlNode For Each ageNode In ageList ageNode.InnerText = (Integer.Parse(ageNode.InnerText) + 1).ToString() Next Dim addressList As XmlNodeList = document.GetElementsByTagName("address", xmlns) Dim i As Integer For i = 0 To addressList.Count - 1 Dim warnComment As XmlComment = document.CreateComment("住所情報は削除されました") addressList.Item(i).ParentNode.ReplaceChild(warnComment, addressList.Item(i)) Next document.Save("c:\sample2.xml") End Sub