TreeView su Multithreading

Public Class Form1

Dim FilePath

Dim FolderNode As TreeNode

Delegate Function UpdateTree(ByVal nodeName As String, ByVal CurrentNode As TreeNode) As TreeNode

Public UpdateTreeDelegate As UpdateTree

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click

FilePath = "D:\Pons\bck"

UpdateTreeDelegate = New UpdateTree(AddressOf AddNode)

FolderNode = TreeView1.Nodes.Add("Projects")

FolderNode.ExpandAll()

Dim thre As New Thread(New ThreadStart(AddressOf LoadTreeView))

thre.Start()

LoadListBox(FilePath)

'LoadTreeView()

End Sub

Private Sub LoadTreeView()

LoadTreeView(FilePath, FolderNode)

End Sub

Private Sub LoadTreeView(ByVal CurrentPath As String, ByVal CurrentNode As TreeNode)

For Each FileInCurrentPath In My.Computer.FileSystem.GetFiles(CurrentPath)

TreeView1.Invoke(UpdateTreeDelegate, New Object() {FileInCurrentPath, CurrentNode})

Application.DoEvents()

Next

For Each FolderInCurrentPath In My.Computer.FileSystem.GetDirectories(CurrentPath)

Dim FolderNode = DirectCast(TreeView1.Invoke(UpdateTreeDelegate, New Object() {FolderInCurrentPath, CurrentNode}), TreeNode)

LoadTreeView(FolderInCurrentPath, FolderNode)

Next

End Sub

Private Function AddNode(ByVal nodeName As String, ByVal CurrentNode As TreeNode) As TreeNode

Return CurrentNode.Nodes.Add(nodeName)

End Function

Private Sub LoadListBox(ByVal CurrentPath As String)

For Each FileInCurrentPath In My.Computer.FileSystem.GetFiles(CurrentPath)

ListBox1.Items.Add(FileInCurrentPath)

Application.DoEvents()

Label1.Text = "file added " + FileInCurrentPath

Next

For Each FolderInCurrentPath In My.Computer.FileSystem.GetDirectories(CurrentPath)

ListBox1.Items.Add(FolderInCurrentPath)

LoadListBox(FolderInCurrentPath)

Next

End Sub

End Class