parsing tcx document using xdocument selectsinglenode - vb.net

Question

I am trying to parse an TCX document similiar to the one used in this post: Import TCX into R using XML package
Only I'm trying to use XmlDocument.SelectNodes and SelectSingleNode instead of getNodeSet. The line with xmlns looks like this:
<TrainingCenterDatabase xmlns="http://www.garmin.com/xmlschemas/TrainingCenterDatabase/v2" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.garmin.com/xmlschemas/TrainingCenterDatabase/v2 http://www.garmin.com/xmlschemas/TrainingCenterDatabasev2.xsd">
If I remove the xmlns and just have , I can parse it without any problems.
My (vb.net) code:
Dim tcxXmlDocument As New System.Xml.XmlDocument()
tcxXmlDocument.Load(tcxFile)
Dim xmlnsManager = New System.Xml.XmlNamespaceManager(tcxXmlDocument.NameTable)
Dim trackpoints As New List(Of Trackpoint)
For Each tpXml As System.Xml.XmlNode In tcxXmlDocument.SelectNodes("//Trackpoint", xmlnsManager)
Dim newTrackpoint As New Trackpoint
With newTrackpoint
.Time = tpXml.SelectSingleNode("Time").InnerText
.LatitudeDegrees = tpXml.SelectSingleNode("Position/LatitudeDegrees").InnerText
.LongitudeDegrees = tpXml.SelectSingleNode("Position/LongitudeDegrees").InnerText
.HeartRateBpm = tpXml.SelectSingleNode("HeartRateBpm").InnerText
End With
trackpoints.Add(newTrackpoint)
Next
How can I configure the XmlNamespaceManager so that I can access the nodes in such a tcx document?
Thanks,
Jason

Answer 1

Use the XmlNamespaceManager.AddNamespace() method to associate a preffix (say "x") with the namespace "http://www.garmin.com/xmlschemas/TrainingCenterDatabase/v2".
Then in your XPath expression, pefix every element name with the "x" prefix.
Replace this:
//Trackpoint
with:
//x:Trackpoint
Replace this:
Time
with:
x:Time
Replace this:
Position/LatitudeDegrees
with:
x:Position/x:LatitudeDegrees
Replace this:
Position/LongitudeDegrees
with:
x:Position/x:LongitudeDegrees
Finally, replace this:
HeartRateBpm
with:
x:HeartRateBpm