public void Insert(int index, DataGridViewColumn item)
 {
     header.insertBefore(item.Element, (Node)header.childNodes[index]);
     _controls.Insert(index, item);
 }
 public void Insert(int index, DataRow item)
 {
     body.insertBefore(item.Element, (Node)body.childNodes[index]);
     _controls.Insert(index, item);
 }