Solution To "Old school tree display"

// My solution to the challenge posted here:
// http://blogs.msdn.com/b/ericlippert/archive/2010/09/09/old-school-tree-display.aspx
// by Allon Guralnek

public static void PrintTree(Node root)
{
    PrintTreeInternal(root, null, false);
}
private static void PrintTreeInternal(Node node, string treeTrunk, bool isLastSibling)
{
    if (treeTrunk != null)
        Console.WriteLine(treeTrunk + (isLastSibling ? "└─" : "├─") + node.Text);
    else
        Console.WriteLine(node.Text);    // When 'treeTrunk' is null, 'node' is the root.


    for (int i = 0; i < node.Children.Count; i++)
    {
        Node child = node.Children[i];
        string nextTreeTrunk;
        bool isLastChild = i == node.Children.Count - 1;

        if (treeTrunk == null)
        {
            nextTreeTrunk = "";
        }
        else
        {
            if (isLastSibling)
                nextTreeTrunk = treeTrunk + "  ";
            else
                nextTreeTrunk = treeTrunk + "│ ";
        }

        PrintTreeInternal(child, nextTreeTrunk, isLastChild);
    }
}