Reading XML childnodes in VB 2010

Question

Hello there,
I am new to XML. Trying to read the childnode "instance". This has been kicking my butt and I can't seem to figure it out. Here is a snippet of the XML file:
xml version="1.0" encoding="utf-8" ?>
- TestData.xml stores hardware and software configuration information from the Win32 Classes of the WMI root\CIMV2 namespace   -->
f(clean);
- root >
- class Name =" Win32_DiskDrive " >
- instance Name =" \.\PHYSICALDRIVE0 " >
properties BytesPerSector =" 512 " FirmwareRevision =" 3.AHG " InterfaceType =" IDE " Model =" ST3320820AS ATA Device " Partitions =" 1 " SCSIPort =" 1 " SectorsPerTrack =" 63 " />
instance >
- instance Name =" \.\PHYSICALDRIVE1 " >
properties BytesPerSector =" 512 " FirmwareRevision =" 8.01 " InterfaceType =" IDE " Model =" ST380013A ATA Device " Partitions =" 2 " SCSIPort =" 0 " SectorsPerTrack =" 63 " />
instance >
- instance Name =" \.\PHYSICALDRIVE2 " >
properties BytesPerSector =" 512 " FirmwareRevision =" 8.01 " InterfaceType =" IDE " Model =" ST380013A ATA Device " Partitions =" 2 " SCSIPort =" 0 " SectorsPerTrack =" 63 " />
instance >
class >
root >
When I run the code it returns the following:
"Node Name: "
I am trying to get it to return the values of the "instance" node (ei. "\.\PHYSIVALDRIVE0", "\.\PHYSIVALDRIVE1" or "\.\PHYSIVALDRIVE2"
Here is the code. I know the For..Next loop is correct because it does loop 3 times and that's how many "instance" nodes exist, but I can't get it to return the values of "instance"
Dim sClass As String = "Win32_DiskDrive"
Dim XMLFile As String = "C:\Temp\XML\TestData.xml"
Dim xmlDoc As New XmlDocument
xmlDoc.Load(XMLFile)
Dim node As XmlNode = xmlDoc.SelectSingleNode( "/root/class[@Name='" & sClass & "']" )
If node IsNot Nothing Then
For Each instance As XmlNode In node.ChildNodes
Console .WriteLine( "Node Name: " & instance.InnerXml)
Next
End If
Below is the code to write the XML in case maybe somethings wrong there:
Dim XMLFile As String = "C:\Temp\XML\TestData.xml"
Dim writer As New XmlTextWriter (XMLFile, System.Text. Encoding .UTF8)
Try
writer.WriteStartDocument()
writer.Formatting = Formatting .Indented
writer.Indentation = 5
writer.WriteComment( "TestData.xml stores hardware and software configuration information from the Win32 Classes of the WMI root\CIMV2 namespace" )
writer.WriteStartElement( "root" ) 'create root node
writer.WriteStartElement( "class" ) 'create class node
writer.WriteAttributeString( "Name" , "Win32_DiskDrive" )
writer.WriteStartElement( "instance" ) 'create instance node
writer.WriteAttributeString( "Name" , "\.\PHYSICALDRIVE0" )
writer.WriteStartElement( "properties" ) 'create properties node
writer.WriteAttributeString( "BytesPerSector" , "512" )
writer.WriteAttributeString( "FirmwareRevision" , "3.AHG" )
writer.WriteAttributeString( "InterfaceType" , "IDE" )
writer.WriteAttributeString( "Model" , "ST3320820AS ATA Device" )
writer.WriteAttributeString( "Partitions" , "1" )
writer.WriteAttributeString( "SCSIPort" , "1" )
writer.WriteAttributeString( "SectorsPerTrack" , "63" )
writer.WriteEndElement() 'close the instance node
writer.WriteEndElement() 'close the class node
writer.WriteStartElement( "instance" ) 'create instance node
writer.WriteAttributeString( "Name" , "\.\PHYSICALDRIVE1" )
writer.WriteStartElement( "properties" ) 'create properties node
writer.WriteAttributeString( "BytesPerSector" , "512" )
writer.WriteAttributeString( "FirmwareRevision" , "8.01" )
writer.WriteAttributeString( "InterfaceType" , "IDE" )
writer.WriteAttributeString( "Model" , "ST380013A ATA Device" )
writer.WriteAttributeString( "Partitions" , "2" )
writer.WriteAttributeString( "SCSIPort" , "0" )
writer.WriteAttributeString( "SectorsPerTrack" , "63" )
writer.WriteEndElement() 'close the instance node
writer.WriteEndElement() 'close the class node
writer.WriteStartElement( "instance" ) 'create instance node
writer.WriteAttributeString( "Name" , "\.\PHYSICALDRIVE2" )
writer.WriteStartElement( "properties" ) 'create properties node…

Hirendra Sisodiya · Accepted Answer

hello thomas
you need to value of name ei. "\.\PHYSIVALDRIVE0", "\.\PHYSIVALDRIVE1" or \.\PHYSIVALDRIVE2
these are values of attribute 'name' of elememt 'Instance' . so you need to apply this code
:
Dim sClass As String = "Win32_DiskDrive"
Dim XMLFile As String = "C:\Temp\XML\TestData.xml"
Dim xmlDoc As New XmlDocument
xmlDoc.Load(XMLFile)
Dim node As XmlNode = xmlDoc.SelectSingleNode( "/root/class[@Name='" & sClass & "']" )
If node IsNot Nothing Then
For Each instance As XmlNode In node.ChildNodes
For i As Integer = 0 To instance.Attributes.Count - 1
Dim A As XmlAttribute = instance.Attributes.Item(i)
Console .WriteLine (A.Value)
Next
thanks
Plese mark as answer if it helps
Next
End If

Thomas Traylor · Answer

Thank you, hirendra