Question

I have a XPath expression that is supposed to return/get only one node out of the XML document. But it is getting more than the one. I don’t understand why.

Code-behind:

Dim xmlNameTbl As XmlNameTable = rootDoc.NameTable
Dim xmlNS As XmlNamespaceManager = New XmlNamespaceManager(xmlNameTbl)
xmlNS.AddNamespace("asp", "http://test.com/asp")

Dim sectionPosition As String = rowNode.GetAttribute("ID")
'In this example sectionPosition is "A03"

Dim sectionLetter As String = rowNode.GetAttribute("ID").Substring(0, 1)
Dim sectionRowNumberText As String = rowNode.GetAttribute("ID").Remove(0, 1)
Dim sectionRowNumber As Integer
Integer.TryParse(sectionRowNumberText, sectionRowNumber)

Dim addingNav As XPathNavigator = rootDoc.CreateNavigator

Dim hello = rootDoc.ChildNodes

Dim addingItr As XPathNodeIterator = addingNav.Select("//asp:TableRow[@ID='" & sectionPosition & "']", xmlNS)
'Nodes with A03 and A02 are being returned, even though it should be only A03 returned

XML Document:

<?xml version="1.0" encoding="utf-8"?>
<Root xmlns:asp="http://test.com/asp" xmlns:meta="http://test.com/meta" xmlns:cc1="http://test.com/cc1">
  <asp:TableRow ID="A03">
    <asp:TableCell>
      <asp:Localize ID="tagthreeCtrlNumberRes" meta:resourcekey="tagthreeCtrlNumberRes" runat="server" />
    </asp:TableCell>
    <asp:TableCell>
      <asp:Localize ID="tagthreeCtrlDescRes" meta:resourcekey="tagthreeCtrlDescRes" runat="server" />
      <asp:Localize ID="tagthreeCtrlNoteRes" meta:resourcekey="tagthreeCtrlNoteRes" runat="server" />
    </asp:TableCell>
    <asp:TableCell>
      <asp:RadioButtonList ID="rblthreeCtrlRes0" RepeatDirection="Horizontal" runat="server">
        <asp:ListItem Text="Yes" meta:resourcekey="rblthreeCtrl0Res0" Value="1" />
        <asp:ListItem Text="No" meta:resourcekey="rblthreeCtrl1Res0" Value="0" />
        <asp:ListItem Text="N/A" meta:resourcekey="rblthreeCtrl2Res0" Value="2" />
      </asp:RadioButtonList>
      <asp:RadioButtonList ID="rblthreeCtrlRes1" RepeatDirection="Horizontal" runat="server">
        <asp:ListItem Text="Yes" meta:resourcekey="rblthreeCtrl0Res1" Value="1" />
        <asp:ListItem Text="No" meta:resourcekey="rblthreeCtrl1Res1" Value="0" />
        <asp:ListItem Text="N/A" meta:resourcekey="rblthreeCtrl2Res1" Value="2" />
      </asp:RadioButtonList>
    </asp:TableCell>
    <asp:TableCell>
      <asp:Button ID="cmdthreeCtrlRes" meta:resourcekey="cmdthreeCtrlRes" runat="server" OnClick="FormDataSave_Click" />
    </asp:TableCell>
    <asp:TableCell>
      <asp:Localize ID="lblAssmthreeCtrlRes" meta:resourcekey="lblAssmthreeCtrlRes" runat="server" />
    </asp:TableCell>
    <asp:TableCell>
      <asp:Localize ID="lblQualthreeCtrlRes" meta:resourcekey="lblQualthreeCtrlRes" runat="server" />
      <asp:Button ID="cmdQualAcceptthreeCtrlRes" meta:resourcekey="cmdQualAcceptthreeCtrlRes" OnClick="cmdQualAccept_Click" runat="server" Text="Accept" Visible="True" />
    </asp:TableCell>
    <asp:TableCell />
    <asp:TableCell />
  </asp:TableRow>
  <asp:TableRow ID="A04">
    <asp:TableCell>
      <asp:Localize ID="tagoneCtrlNumberRes" meta:resourcekey="tagoneCtrlNumberRes" runat="server" />
    </asp:TableCell>
    <asp:TableCell>
      <asp:Localize ID="tagoneCtrlDescRes" meta:resourcekey="tagoneCtrlDescRes" runat="server" />
      <asp:Localize ID="tagoneCtrlNoteRes" meta:resourcekey="tagoneCtrlNoteRes" runat="server" />
    </asp:TableCell>
    <asp:TableCell>
      <asp:Localize ID="tagtxtoneCtrlRes0" meta:resourcekey="tagtxtoneCtrlRes0" runat="server" />
      <asp:Textbox ID="txtoneCtrlRes0" runat="server" />
    </asp:TableCell>
    <asp:TableCell>
      <asp:Button ID="cmdoneCtrlRes" meta:resourcekey="cmdoneCtrlRes" runat="server" OnClick="FormDataSave_Click" />
    </asp:TableCell>
    <asp:TableCell>
      <asp:Localize ID="lblAssmoneCtrlRes" meta:resourcekey="lblAssmoneCtrlRes" runat="server" />
    </asp:TableCell>
    <asp:TableCell />
    <asp:TableCell />
    <asp:TableCell />
  </asp:TableRow>
  <asp:TableRow ID="A02">
    <asp:TableCell>
      <asp:Localize ID="tagtwoCtrlNumberRes" meta:resourcekey="tagtwoCtrlNumberRes" runat="server" />
    </asp:TableCell>
    <asp:TableCell>
      <asp:Localize ID="tagtwoCtrlDescRes" meta:resourcekey="tagtwoCtrlDescRes" runat="server" />
      <asp:Localize ID="tagtwoCtrlNoteRes" meta:resourcekey="tagtwoCtrlNoteRes" runat="server" />
    </asp:TableCell>
    <asp:TableCell>
      <asp:Localize ID="tagtxttwoCtrlRes0" meta:resourcekey="tagtxttwoCtrlRes0" runat="server" />
      <asp:Textbox ID="txttwoCtrlRes0" runat="server" />
    </asp:TableCell>
    <asp:TableCell>
      <asp:Button ID="cmdtwoCtrlRes" meta:resourcekey="cmdtwoCtrlRes" runat="server" OnClick="FormDataSave_Click" />
    </asp:TableCell>
    <asp:TableCell>
      <asp:Localize ID="lblAssmtwoCtrlRes" meta:resourcekey="lblAssmtwoCtrlRes" runat="server" />
    </asp:TableCell>
    <asp:TableCell />
    <asp:TableCell />
    <asp:TableCell />
  </asp:TableRow>
</Root>

Answer 1

I cannot find anything wrong with the above code/XML.

Running your example works as expected, with addingItr.Count returning 1.

I double checked this by iterating the returned nodes like so:

For Each n As XPathNavigator In addingItr
    Dim nodeName As String = n.Name
Next

What code are you running to determine the count of the returned nodes?

Edit

From: XPathNodeIterator Class

An XPathNodeIterator object returned by the XPathNavigator class is
not positioned on the first node in a selected set of nodes. A call to
the MoveNext method of the XPathNodeIterator class must be made to
position the XPathNodeIterator object on the first node in the
selected set of nodes.

So what you are seeing when debugging is the InnerXml property of the root node.