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A simple method to implement infinite classification in PHP, infinite classification in php_PHP tutorial
A simple method to implement infinite classification in PHP, infinite classification in php_PHP tutorial
Jul 12, 2016 am 08:51 AM
A simple method to implement infinite-level classification in PHP, unlimited-level classification in PHP
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);
Readers who are interested in more PHP-related content can check out the special topics on this site: "Complete PHP Array Operation Skills", "Summary of PHP Sorting Algorithms", "Summary of PHP Common Traversal Algorithms and Techniques", "PHP Data Structure and Algorithm Tutorial", "php Programming Algorithm Summary", "PHP Mathematical Operation Skills Summary", "php Regular Expression Usage Summary", "PHP Operations and Operator Usage Summary", "php String Usage Summary" 》and《Summary of common database operation skills in php》
I hope this article will be helpful to everyone in PHP programming.
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