Home > Article > Backend Development > A simple method to implement infinite classification in PHP, infinite classification in php_PHP tutorial
The example in this article describes a simple method to implement infinite-level classification in PHP. Share it with everyone for your reference, the details are as follows:
Database structure:
CREATE TABLE IF NOT EXISTS `city` ( `id` int(11) NOT NULL auto_increment, `name` varchar(30) character set utf8 collate utf8_unicode_ci NOT NULL default '0', `parentId` int(11) NOT NULL default '0' PRIMARY KEY (`id`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 AUTO_INCREMENT=7 ;
php file:
$db=new DB($Config['host'],$Config['user'],$Config['password'],$Config['port'],$Config['db'],$Config['charset']); function findCity($table,$id=0,$level=1){ global $db; $findSql="select id,name,parentId from $table where parentId={$id} order by id"; $findResult=$db->getArray($findSql); $num=$db->numRows; $logoStr="|"; for($i=0;$i<$level;$i++){ $logoStr.="--"; } if($num!=0){ for($j=0;$j<$num;$j++){ echo "<option value={$findResult[$j]['id']}>{$logoStr}{$findResult[$j][name]}</option>"; findCity($table,$findResult[$j]['id'],$level+1); } } } findCity(city);
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I hope this article will be helpful to everyone in PHP programming.