delphi treeview添加节点

procedure TForm1.Button1Click(Sender: TObject);

var
MyTreeNode1, MyTreeNode2: TTreeNode;
begin
with TreeView1.Items do
begin
Clear; { remove any existing nodes }
MyTreeNode1 := Add(nil, 'RootTreeNode1'); { Add a root node }
{ Add a child node to the node just added }
AddChild(MyTreeNode1,'ChildNode1');

{Add another root node}
MyTreeNode2 := Add(MyTreeNode1, 'RootTreeNode2');
{Give MyTreeNode2 to a child }
AddChild(MyTreeNode2,'ChildNode2');

{Change MyTreeNode2 to ChildNode2 }
{ and add a child node to it}
MyTreeNode2 := TreeView1.Items[3];
AddChild(MyTreeNode2,'ChildNode2a');

{Add another child to ChildNode2, after ChildNode2a }
Add(MyTreeNode2,'ChildNode2b');

{add another root node}
Add(MyTreeNode1, 'RootTreeNode3');
end;