Occurs after the tree node is collapsed.
Assembly: System.Windows.Forms (in System.Windows.Forms.dll)
The following code example updates all the child tree nodes of a TreeNode when the user changes its checked state. This code requires that you have a Form with a TreeView that has TreeNode objects in its TreeNodeCollection. The TreeNodeCollection should have tree nodes with child nodes.
' Updates all child tree nodes recursively. Private Sub CheckAllChildNodes(treeNode As TreeNode, nodeChecked As Boolean) Dim node As TreeNode For Each node In treeNode.Nodes node.Checked = nodeChecked If node.Nodes.Count > 0 Then ' If the current node has child nodes, call the CheckAllChildsNodes method recursively. Me.CheckAllChildNodes(node, nodeChecked) End If Next node End Sub ' NOTE This code can be added to the BeforeCheck event handler instead of the AfterCheck event. ' After a tree node's Checked property is changed, all its child nodes are updated to the same value. Private Sub node_AfterCheck(sender As Object, e As TreeViewEventArgs) Handles treeView1.AfterCheck ' The code only executes if the user caused the checked state to change. If e.Action <> TreeViewAction.Unknown Then If e.Node.Nodes.Count > 0 Then ' Calls the CheckAllChildNodes method, passing in the current ' Checked value of the TreeNode whose checked state changed. Me.CheckAllChildNodes(e.Node, e.Node.Checked) End If End If End Sub