by Chetan Sarva (5 Submissions)
Category: Files/File Controls/Input/Output
Compatability: Visual Basic 3.0
Difficulty: Intermediate
Date Added: Wed 3rd February 2021
Rating: 
(3 Votes)
These are two functions I wrote to save and load a treeview's nodes (saves the .text, .tag, and .key properties) to and from a text file.
This is a very simple code and should be very easy to incorporate to any project.
Inputs
No inputs...
Assumes
None needed...
Code Returns
Doesn't return anything...
Side Effects
No side effects...
API DeclarationsNo API's used here...
VBcodersPublic Sub LoadTree(ByVal tvTree As TreeView, ByVal sFileName As String)
' Function by Chetan Sarva (November 17, 1999)
' Please include this comment if you use this code.
Dim curNode As Node
Dim sDelimiter As String
Dim freef As Integer
Dim buf As String
Dim nodeparts As Variant
sDelimiter = " " ' We want something extremely unique to delimit
' each of the pices of our treeview
On Error Resume Next
' Get a free file and open our file for output
freef = FreeFile()
Open sFileName For Input As #freef
Do
DoEvents
' Read in the current line
Line Input #freef, buf
' Split the line into pieces on our delimiter
nodeparts = Split(buf, sDelimiter)
' See if it's a root or child node and add accordingly
If nodeparts(3) = "parent" Then
curNode = tvTree.Nodes.Add(, , nodeparts(1), nodeparts(0))
curNode.Tag = nodeparts(2)
Else
curNode = tvTree.Nodes.Add(nodeparts(3), tvwChild, nodeparts(1), nodeparts(0))
curNode.Tag = nodeparts(2)
End If
Loop Until EOF(freef)
Close #freef
End Sub
Public Sub SaveTree(ByVal tvTree As TreeView, ByVal sFileName As String)
' Function by Chetan Sarva (November 17, 1999)
' Please include this comment if you use this code.
Dim curNode As Node
Dim sDelimiter As String
Dim freef As Integer
sDelimiter = " " ' We want something extremely unique to delimit
' each of the pices of our treeview
On Error Resume Next
' Get a free file and open our file for output
freef = FreeFile()
Open sFileName For Output As #freef
' Loop through all the nodes and save all the
' important information
For Each curNode In tvTree.Nodes
If curNode.FullPath = curNode.Text Then
Print #freef, curNode.Text; sDelimiter; curNode.Key; sDelimiter; curNode.Tag; sDelimiter; "parent"
Else
Print #freef, curNode.Text; sDelimiter; curNode.Key; sDelimiter; curNode.Tag; sDelimiter; curNode.Parent.Key
End If
Next curNode
Close #freef
End Sub