[RESOLVED] Question about node of treeview.

[manhit45]

How can i know selectednode of treeview is rootnode or childnode or child of childnode.

[jmcilhinney]

Have you read the documentation for the TreeNode class? If you have then you know what properties it has so you know the answer to your question.

[manhit45]

I read that document so i can solve that problem like this :

Dim Count As Integer = mytreeview.SelectedNode.GetNodeCount(True)
if count = 0 then
Msgbox(mytreeview.SelectedNode.FullPath & " is last child node")
End if

But i want to check all nodes for determine what class of node does it belong to ?

[jmcilhinney]

So, are you saying that you don't know how to traverse the tree? If so then the answer is with recursion. A tree is an inherently recursive structure so recursion is the best way to traverse a tree is using recursion. In the case of a TreeView you can do it like so:

Private Sub ProcessNodes(ByVal nodes As TreeNodeCollection)
    For Each node As TreeNode In nodes
        'Process node, e.g.
        MessageBox.Show(node.FullPath)
 
        'Process child nodes.
        Me.ProcessNodes(node.Nodes)
    Next
End Sub

Obviously displaying the full path in a message box is just an example but you can process the node in any way you see fit. You would start the ball rolling by call that method and passing the Nodes property of your TreeView. It will then visit every node in the tree.

Note that that code will perform a depth-first search, i.e. the node's children are processed before it siblings. It's the most natural so it should be your first choice. If you specifically need a breadth-first search though:

Private Sub ProcessNodes(ByVal nodes As TreeNodeCollection)
    For Each node As TreeNode In nodes
        'Process node, e.g.
        MessageBox.Show(node.FullPath)
    Next
 
    For Each node As TreeNode In nodes
        'Process child nodes.
        Me.ProcessNodes(node.Nodes)
    Next
End Sub

You might also want to take note of the TreeNode.Level property, which is included in the documentation.

[manhit45]

You might also want to take note of the TreeNode.Level property, which is included in the documentation.

That is which i want to. and i did it. thanks .