TreeNodes Made EZ

[spyk3]

Came up with some simple to use treenode subs that simply require 2 simple things:
1. a path, usually as a computer path, but you could easily trick it out and datatable paths (it would require a few very simple changes everywhere you see Directory.GetDirectories)
2. the second sub simply needs to be placed in the treeview's BeforeExpand event

Everything is broke down so it is very easy to follow and see what's going on, i'll add comments after lunch if i get a chance, i'm basically killing time for coffee to finish making for now.

Simply add the first sub to your form load event with:

populateTreeView(yourTreeView, yourPath)

First Sub:

Public Sub populateTreeView(ByVal _treeView As TreeView, ByVal _path As String)
        Try
 
            For Each dirParent As String In Directory.GetDirectories(_path)
                Dim parentNode As New TreeNode(dirParent.Substring(_path.Length + 1))
                trvMain.Nodes.Add(parentNode)
 
                Try
 
                    'Works for Music/Pics/Video Folders in Windows 7/Vista
                    If dirParent.Contains("Documents") Then
                        If dirParent.Contains("Music") Then
                            dirParent = dirParent.Replace("Documents\My ", "")
                        End If
                        If dirParent.Contains("Pictures") Then
                            dirParent = dirParent.Replace("Documents\My ", "")
                        End If
                        If dirParent.Contains("Videos") Then
                            dirParent = dirParent.Replace("Documents\My ", "")
                        End If
                    End If
 
                    For Each dirChild As String In Directory.GetDirectories(dirParent)
 
                        Dim path As String
 
                        Try
 
                            path = dirParent
                            Dim childNode As New TreeNode(dirChild.Substring(dirParent.Length + 1))
                            parentNode.Nodes.Add(childNode)
 
                        Catch ex As Exception
                            Dim exMessage As String = ex.Message & Environment.NewLine
                            'RelayException
                        End Try
 
                    Next
 
                Catch ex As Exception
                    Dim exMessage As String = ex.Message & Environment.NewLine
                     'RelayException
                End Try
 
            Next
 
        Catch ex As Exception
            Dim exMessage As String = ex.Message & Environment.NewLine
             'RelayException
        End Try
    End Sub

Simply add the second sub to your treeview BeforeExpand event with:

populateSubTreeView(e.node, yourPath)

Second Sub:

Public Sub populateSubTreeView(ByVal eNode As TreeNode, ByVal _path As String)
        Try
 
            Dim newPath As String = _path
            If Not eNode.FullPath Is Nothing Then
                newPath = String.Concat(newPath, "\", eNode.FullPath)
 
                Try
 
                    For Each child In eNode.Nodes
                        Dim subNode As String = child.FullPath.Substring(eNode.FullPath.Length + 1)
                        Dim subPath As String = String.Concat(newPath, "\", subNode)
 
                        Try
 
                            For Each folder In Directory.GetDirectories(subPath)
                                Dim childNode As New TreeNode(folder.Substring(subPath.Length + 1))
                                child.Nodes.Add(childNode)
                            Next
 
                        Catch ex As Exception
                            Dim exMessage As String = ex.Message
                            'RelayException
                        End Try
 
                    Next
 
                Catch ex As Exception
                    Dim exMessage As String = ex.Message
                    'RelayException
                End Try
 
            End If
 
        Catch ex As Exception
            Dim exMessage As String = ex.Message
            'RelayException
        End Try
    End Sub

HINT: use ctrl+f to replace all the 'RelayException marks with your own way (exp. Console.WriteLine(exMessage))

[virtueone]

I wanted to build my own FileView/TreeView, but didn't really know how to get started, so this helped ALOT, but your code as-is has a couple problems....

- note: System.IO needs to be imported.
- the string "trvMain" needs to be replaced with the var name "_treeView"
-

Dim parentNode As New TreeNode(dirParent.Substring(_path.Length + 1))

....should be....

Dim parentNode As New TreeNode(dirParent.Substring(_path.Length))

Otherwise, this appears to work great. Thanks for your help.

[virtueone]

Also, in some cases, duplicate entries/nodes appear in the treeview. Do you know why this is happening? I have not made any other changes to the code, (not including the changes from my previous post). Thanks!