How To Populate a Treeview Control with an XML File (244954)



The information in this article applies to:

  • Microsoft Visual Basic Learning Edition for Windows 5.0
  • Microsoft Visual Basic Learning Edition for Windows 6.0
  • Microsoft Visual Basic Professional Edition for Windows 5.0
  • Microsoft Visual Basic Professional Edition for Windows 6.0
  • Microsoft Visual Basic Enterprise Edition for Windows 5.0
  • Microsoft Visual Basic Enterprise Edition for Windows 6.0
  • Microsoft XML 4.0
  • Microsoft XML 2.0
  • Microsoft XML 2.5
  • Microsoft XML 2.6
  • Microsoft XML 3.0

This article was previously published under Q244954

SUMMARY

For a Microsoft Visual Basic .NET version of this article, see 308063.
This article illustrates how to populate a Treeview control from an XML file in Visual Basic.

MORE INFORMATION

Step by Step Example

Note The sample code provided in this article contains a reference to MSXML 2.0.

If a newer version of MSXML has been installed in side-by-side mode, you must explicitly use the Globally Unique Identifiers (GUIDs) or ProgIDs for that version to run the sample code. For example, MSXML version 4.0 can only be installed in side-by-side mode. For additional information about the code changes that are required to run the sample code with the MSXML 4.0 parser, click the following article number to view the article in the Microsoft Knowledge Base:

305019 INFO: MSXML 4.0 Specific GUIDs and ProgIds

If a newer version of MSXML has been installed in side-by-side mode on your machine, the code may use the older version.
  1. Paste following XML code into an empty text file and save the file as Sample.xml:
    <?xml version="1.0"?>
       <family>
       <parent>id="grandfather"
           <parent>id="father"
                <parent>id="brother"
                   <child>id="niece"
                   </child>
                </parent>
                <parent>id="me"
                   <child>id="son"</child>
                   <child>id="daughter"</child>
                </parent>
                <child>id="sister"</child>
            </parent>
            <parent>id="uncle"
                <parent>id="cousin sister"
                   <child>id="second cousin"</child>
                </parent>
                <child>id="cousin brother"</child>
            </parent>
       </parent>
       </family>
    					
  2. Create a Standard EXE project in Visual Basic. Form1 is added by default.
  3. From the Project menu, choose References, and add a reference to Microsoft XML, version 2.0.
  4. From the Project menu, choose Components, and add the Microsoft Windows Common Controls to the project.
  5. Add a command button, a text box, a label, and a Treeview control to the form.
  6. Paste the following code into Form1:
       Option Explicit
       Dim XMLDoc As MSXML.DOMDocument
    
       'To use a newer version of MSXML parser, use a declaration like the   
       'following with the appropriate version in the ProgID. Same applies to the 
       'other sections of the code:
       'Dim XMLDoc As MSXML2.DOMDocument40
    
    Private Sub Form_Load()
        Form1.Move 0, 0, 5565, 4495
        Command1.Move 120, 600, 1335, 375
        Text1.Move 1560, 120, 3735, 285
        Label1.Move 120, 120, 1575, 285
        TreeView1.Move 120, 1080, 5175, 2895
        Command1.Caption = "Load XML File"
        Label1.Caption = "Enter path:"
        Text1.Text = App.Path & "\Sample.XML"
        Form1.Caption = "Load XML File Sample"
    End Sub
    
    Private Sub Command1_Click()
        Set XMLDoc = New DOMDocument
        XMLDoc.async = False
        'XMLDoc.validateOnParse = False
        'If validation is not important, skip it
        XMLDoc.Load Text1.Text
        
        If XMLDoc.parseError.errorCode = 0 Then
            MsgBox "Succeeded"
            If XMLDoc.readyState = 4 Then
                TreeView1.Nodes.Clear
                AddNode XMLDoc.documentElement
            End If
        Else
            MsgBox XMLDoc.parseError.reason & vbCrLf & _
            XMLDoc.parseError.Line & vbCrLf & _
            XMLDoc.parseError.srcText
        End If
        
    End Sub
    
    Private Sub AddNode(ByRef XML_Node As IXMLDOMNode, _
                        Optional ByRef TreeNode As Node)
        Dim xNode As Node
        Dim xNodeList As IXMLDOMNodeList
        Dim i As Long
        
        If TreeNode Is Nothing Then
            Set xNode = TreeView1.Nodes.Add
        Else
            Set xNode = TreeView1.Nodes.Add(TreeNode, tvwChild)
        End If
        
        xNode.Expanded = True
        xNode.Text = XML_Node.nodeName
        
        If xNode.Text = "#text" Then
            xNode.Text = XML_Node.nodeTypedValue
        Else
            xNode.Text = "<" + xNode.Text + ">"
        End If
        
        Set xNodeList = XML_Node.childNodes
        For i = 0 To xNodeList.length - 1
            AddNode xNodeList.Item(i), xNode
        Next
    End Sub
    					
  7. Run the project.
  8. Type the path to Sample.xml, and then click the command button.

Modification Type:MinorLast Reviewed:7/1/2004
Keywords:kbhowto kbTreeView KB244954