PHP implements Infinitus classification graphic tutorial, _PHP tutorial

/**
* @author koma
* @todo PHP Infinitus Classification
*/ $cn = mysql_connect('localhost', 'root', '') or die(mysql_error());
mysql_select_db('t', $cn) or die(mysql_error());
mysql_query('set names utf8');
/**
* Get subclasses from the top level down
* @param number $pid
* @param array $lists
* @param number $deep
* @return array
* / function getLists($pid = 0, &$lists = array(), $deep = 1) {
$sql = 'SELECT * FROM category WHERE pid='.$pid;
$res = mysql_query( $sql);
while ( ($row = mysql_fetch_assoc($res)) !== FALSE ) {
$row['catename'] = str_repeat(' ', $deep).'|--- '.$row['catename'];
$lists[] = $row;
getLists($row['id'], $lists, ++$deep); //Depth before entering the subclass +1                                                                                                                                           and result = getLists($pid);
$str = '';
foreach ( $result as $item ) {
$selected = "";
if ( $selectid = = $item['id'] ) {
               $selected = 'selected'; '].'';
}
return $str .= '';
} /**
* Start from the subclass and get its parent class step by step
* @param number $cid
* @param array $category
* @return array:
*/ function getCategory($cid, & $category = array()) {
$sql = 'SELECT * FROM category WHERE id='.$cid.' LIMIT 1';
$result = mysql_query($sql);
$row = mysql_fetch_assoc($result);
if ( $row ) {
$category[] = $row;
getCategory($row['pid'], $category);
}
krsort($category); //Reverse order to achieve the effect from parent class to subclass Return $category;
}
function displayCategory($cid) {
$result = getCategory($cid);
$str = "";
foreach ( $result as $item ) {
$str .= ''. $item['catename'].'>';
}
return substr($str, 0, strlen($str) - 1);
}
echo displayLists(0, 3);
echo displayCategory(13);

3, rendering: