並前往https://ljvxj5vhf.pixnet.net/blog/post/146790461-%E5%BF%83%E5%BE%97%E3%80%90tree-walker%E3%80%913x3%E7%B1%B3%E7%82%8A%E4%BA%8B%E5%B8%B3-%E5%AE%A2%E5%BB%B3%E5%B8%B3%E7%94%A8%E5%81%B4%E9%82%8A%E5%9C%8D
