How to add ToolStripMenuItems to a MenuStrip or ContextMenu dynamically

Think about the Office Word application's file menustrip. The files which you last open are listed there. How is this possible? Here is the code:
 

ToolStripMenuItem NEW;
NEW = new ToolStripMenuItem(text);
NEW.Text = text;
NEW.Click += new EventHandler(Item_Click);
NEW.CheckOnClick = true;
MainToolStripMenuItem.DropDown.Items.Add(NEW);

Then you can use the Click event like:

private void Item_Click(object sender, EventArgs e)
{
    if (sender is ToolStripMenuItem)  //Check On Click.
    {
        foreach (ToolStripMenuItem item in (((ToolStripMenuItem)sender).GetCurrentParent().Items))
        {
            if (item == sender)
            {
                txtNoteName.Text = item.Text;
                item.Checked = true;
            }
            if ((item != null) && (item != sender))
                item.Checked = false;
            }
        }
    }