check all items under a parent node in Visual Basic - vb.net

Question

I am trying to check all the childnodes under a parent node, the code I have so far only goes about 2-3 levels deep in the TreeView and I am looking to grab all nodes no matter how deep they are. Could someone shed some insight on this.
Below is the code:
Private Sub CheckChildNode(ByVal currNode As TreeNode)
'set the children check status to the same as the current node
Dim checkStatus As Boolean = currNode.Checked
For Each node As TreeNode In currNode.Nodes
node.Checked = checkStatus
CheckChildNode(node)
Next
End Sub
Private Sub CheckParentNode(ByVal currNode As TreeNode)
Dim parentNode As TreeNode = currNode.Parent
If parentNode Is Nothing Then Exit Sub
parentNode.Checked = True
For Each node As TreeNode In parentNode.Nodes
If Not node.Checked Then
parentNode.Checked = False
Exit For
End If
Next
CheckParentNode(parentNode)
End Sub
Private Sub treeview_AfterCheck(ByVal sender As System.Object, ByVal e As
System.Windows.Forms.TreeViewEventArgs) Handles treeview.AfterCheck
RemoveHandler treeview.AfterCheck, AddressOf treeview_AfterCheck
CheckChildNode(e.Node)
CheckParentNode(e.Node)
AddHandler treeview.AfterCheck, AddressOf treeview_AfterCheck
End Sub

Answer 1

In order to get all subnodes no matter how deep they are, you definitely need recursion.
That is, you take each direct child of a node and do the check for this node. And you also call the method to check subnodes for each child.
So here in Pseudocode.
node getParentNode(node child){
return child.parent
}
node checkNode(node n){
// perform check here for node n
if n is not valid {
return false!
}
// do children recursively
for each child in n.children{
// function calls itself!
checkNode(child)
}
}
Here's a recursion tutorial for vb.net. Here, here and here is you can find additional information.