function getRoot() {
		$r = $this->parent;
		$n = ($r === null) ? null : $r->parent;
		while ($n !== null) {
			$r = $n;
			$n = $r->parent;
		}

		return $r;
	}
function getRoot() {
		$r = $this->parent;
		$n = ($r === null) ? null : $r->parent;
		while ($n !== null) {
			$r = $n;
			$n = $r->parent;
		}

		return $r;
	}
function getRoot ( ) { $ r = $ this -> parent ; $ n = ( $ r === null ) ? null : $ r -> parent ; while ( $ n !== null ) { $ r = $ n ; $ n = $ r -> parent ; } return $ r ; }
Get top parent
@return DomNode Root, null if node has no parent
Get top parent