Private Sub Form_Unload(Cancel As Integer)
  ' 保存现有的值
  SaveValues
End Sub

Private Sub LoadValues()

  Dim xml_document As DOMDocument

  Dim values_node As IXMLDOMNode

  ' 载入文件

  Set xml_document = New DOMDocument
  xml_document.Load p_AppPath & "Online00.xml"
  If xml_document.documentElement Is Nothing Then

    Exit Sub

  End If

  '寻找节点
  Set values_node = xml_document.selectSingleNode("ab")
  ' 读取各个节点的值
  txtName.Text = GetNodeValue(values_node, "k1", "???")
  txtName.Text = GetNodeValue(values_node, "k1", "???")
  txtName.Text = GetNodeValue(values_node, "k1", "???")
End Sub

' 返回各个节点的值

Private Function GetNodeValue(ByVal start_at_node As IXMLDOMNode, ByVal node_name As String, _
Optional ByVal default_value As String = "") As String

  Dim value_node As IXMLDOMNode
  Set value_node = start_at_node.selectSingleNode(".//" & node_name)
  If value_node Is Nothing Then
    GetNodeValue = default_value
  Else
    GetNodeValue = value_node.Text
  End If

End Function

' 保存现有的值

Private Sub SaveValues()
  Dim xml_document As DOMDocument
  Dim values_node As IXMLDOMNode
  ' 建立XML文件
  Set xml_document = New DOMDocument
  Set values_node = xml_document.createElement("ab")
  xml_document.appendChild values_node
  CreateNode values_node, "k1", txtName.Text
  CreateNode values_node, "k1", txtSex.Text
   ' 保存XML文件
  xml_document.save p_AppPath & "Online00.xml"

End Sub

Private Sub CreateNode(ByVal parent As IXMLDOMNode, _
ByVal node_name As String, ByVal node_value As String)
Dim new_node As IXMLDOMNode
  Set new_node = parent.ownerDocument.createElement(node_name)
  new_node.Text = node_value
  parent.appendChild new_node
End Sub