php无限分类实现一二

 1 --
 2 -- Table structure for table `category`
 3 --
 4 
 5 CREATE TABLE IF NOT EXISTS `category` (
 6   `id` int(11) NOT NULL AUTO_INCREMENT,
 7   `catpath` varchar(255) DEFAULT NULL,
 8   `name` varchar(255) DEFAULT NULL,
 9   PRIMARY KEY (`id`)
10 ) ENGINE=MyISAM  DEFAULT CHARSET=utf8 AUTO_INCREMENT=11 ;
11 
12 --
13 -- Dumping data for table `category`
14 --
15 
16 INSERT INTO `category` (`id`, `catpath`, `name`) VALUES
17 (1, '0', '网站首页'),
18 (2, '0-1', 'Linux OS'),
19 (3, '0-1', 'Apache服务器'),
20 (4, '0-1', 'MySQL数据库'),
21 (5, '0-1', 'PHP脚本语言'),
22 (6, '0-1-2', 'Linux 系统教程'),
23 (7, '0-1-2', 'Linux 网络技术'),
24 (8, '0-1-2', 'Linux 安全基础'),
25 (9, '0-1-2-7', 'Linux LAMP'),
26 (10, '0-1-3', 'apache Server');

1 $conn = mysql_connect ( 'localhost', 'root', '' );
 2 mysql_select_db ( 'test', $conn );
 3 mysql_query ( 'set names UTF8' );
 4 $sql = "select id,concat(catpath,'-',id) as abspath,name from category order by abspath";
 5 $query = mysql_query ( $sql );
 6 while ( $row = mysql_fetch_array ( $query ) ) {
 7     /**
 8      * 第一种展示方法
 9      */
10     /*$space = str_repeat ( '    ', count ( explode ( '-', $row ['abspath'] ) ) - 1 );
11     echo $space . $row ['name'] . '<br>';*/
12     /**
13      * 第二种展示方法
14      */
15     $space = str_repeat ( '    ', count ( explode ( '-', $row ['abspath'] ) ) - 1 );
16     $option .= '<option value="' . $row ['id'] . '">' . $space . $row ['name'] . '</option>';
17 }
18 echo '<select name="opt">' . $option . '</select>';

转自：http://www.cnblogs.com/BraveCheng/archive/2011/08/26/brave.html