private static Hashtable ht; // 使用Hashtable来存储享元对象，充当享元池
private IgoChessmanFactory()
{
ht = new Hashtable();
IgoChessman blackChess = new BlackIgoChessman();
ht.Add("b", blackChess);
IgoChessman whiteChess = new WhiteIgoChessman();
ht.Add("w", whiteChess);
}
private static Hashtable ht; //使用Hashtable来存储享元对象，充当享元池
private IgoChessmanFactory()
{
ht = new Hashtable();
IgoChessman black, white;
black = new BlackIgoChessman();
ht.Add("b", black);
white = new WhiteIgoChessman();
ht.Add("w", white);
}