Visual Basic.NET How to Program (PDF)

554 Graphical User Interfaces Concepts: Part 2 Chapter 13
25
26 If directoryArray.Length 0 Then ' if at least one
27
28 Dim currentDirectory As String
29
30 ' for every subdirectory, create new TreeNode,
31 ' add as child of current node and
32 ' recursively populate child nodes with subdirectories
33 For Each currentDirectory In directoryArray
34
35 ' create TreeNode for current directory
36 Dim myNode As TreeNode = _
37 New TreeNode(currentDirectory)
38
39 ' add current directory node to parent node
40 parentNode.Nodes.Add(myNode)
41
42 ' recursively populate every subdirectory
43 PopulateTreeView(currentDirectory, myNode)
44 Next
45
46 End If
47
48 ' catch exception
49 Catch unauthorized As UnauthorizedAccessException
50 parentNode.Nodes.Add("Access Denied")
51 End Try
52
53 End Sub ' PopulateTreeView
54
55 ' called by system when form loads
56 Private Sub FrmTreeViewDirectory_Load(ByVal sender As Object, _
57 ByVal e As System.EventArgs) Handles MyBase.Load
58
59 ' add c:\ drive to treDirectory and insert its subfolders
60 treDirectory.Nodes.Add("C:")
61 PopulateTreeView("C:\", treDirectory.Nodes(0))
62 End Sub ' FrmTreeViewDirectory_Load
63
64 End Class ' FrmTreeViewDirectory
Fig. 13.22 TreeView used to display directories (part 2 of 3).