Treeview and hashtables

[mwcapps]

I have treeview with checkboxes on it and need to update the database(if unchecked) and insert into the database(if checked) in my button click sub routine. I'm using a hashtable to avoid having 'duplicate keys' in run time. I'm obviously doing something very wrong because the code jumps straight from the 'For each' statement to the 'End Sub' line.

Private Sub cmdUpdate_Click(ByVal sender as System.Object, ByVal e as System.EventArgs) Handles cmdUpdate.Click

Dim sUpdate as String = ""
Dim node as TreeNode

For each node in tvQuestions.Nodes
    If node.checked Then
        If node.text = htxref.item(tvQuestions.SelectedNode) Then
           sUpdate = "Update............" 'actual SQL statement too long for here
        Else
           sUpdate = "Insert......" 'actual SQL statement too long for here
        End if
    End if
Next

'SQL execution statements here'
End Sub

[mzmishra]

try to use TreeNodeCollect ion
TreeNodeCollect ion nodes = treeView.Nodes;
foreach (TreeNode n in nodes)
{
}