Question

I have a program with a TreeView list containing Nodes, and Nodes with Children. These all have the checkbox property enables. I need to know how to check what Nodes / node children are checked. So far I have been able to successfully test for the parent nodes, but no children using:

//this  will turn black any node that is checked, doesn't affect the children though
    TreeNodeCollection nodes = this.treeView1.Nodes;
                foreach (TreeNode n in nodes)
                {
                    if (n.Checked)
                    {
                        n.BackColor = Color.Black;   
                    }
                }

How do I get it to check the parent nodes, as well as the children? I have searched and not found anything that cleared this up for me.

Answer 1

You could define a recursive function that will mark all selected items:

private static void MarkSelectedNodes(TreeNodeCollection nodes)
{
    foreach (TreeNode n in nodes)
    {
        if (n.Checked)
            n.BackColor = Color.Black;

        MarkSelectedNodes(n.Nodes);
    }
}

and call it like so:

MarkSelectedNodes(treeView1.Nodes);