点击treeview某一项如何得到它的值？我这样写触发事件为什么不反应？

点击treeview某一项如何得到它的值？
//////////////生成treeview
procedure TForm1.FormCreate(Sender: TObject);
var
 temnode,childnode:TTreeNode;
 i,j:integer;
begin
TreeView1.Items.Clear;
temnode:=TreeView1.Items.Add(TreeView1.Selected,PChar('长城公司'));
adodataset1.first;
while not adodataset1.eof do
begin         childnode:=TreeView1.Items.AddChild(temnode,adodataset1.FieldValues['name']);
TreeView1.Items.AddChild(childnode,'点击查阅..');
adodataset1.next;
end;
adodataset1.first;
end;
end.//////////////触发事件procedure TForm1.treeview1click(Sender: TObject);
var
currentnode:ttreenode;
begin
currentnode:=treeview1.selected;
showmessage('111');
end;
end.