PHP实现无限极分类图文教程

/**
?* @author koma
?* @todo?? PHP无限极分类
?*/ $cn = mysql_connect('localhost','root','') or die(mysql_error());
mysql_select_db('t',$cn) or die(mysql_error());
mysql_query('set names utf8');
?/**
?* 从顶层逐级向下获取子类
?* @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); //进入子类之前深度+1???????? --$deep; //从子类退出之后深度-1???? }
??? return $lists;
}
?function displayLists($pid = 0,$selectid = 1) {
??? $result = getLists($pid);
??? $str = '<select>';
??? foreach ( $result as $item ) {
??????? $selected = "";
??????? if ( $selectid == $item['id'] ) {
??????????? $selected = 'selected';
??????? }
??????? $str .= '<option '.$selected.'>'.$item['catename'].'</option>';
??? }
??? return $str .= '</select>';
} /**
?* 从子类开始逐级向上获取其父类
?* @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); //逆序,到达从父类到子类的效果???? return $category;
}
?function displayCategory($cid) {
??? $result = getCategory($cid);
??? $str = "";
??? foreach ( $result as $item ) {
??????? $str .= '<a href="'.$item['id'].'">'.$item['catename'].'</a>>';
??? }
??? return substr($str,strlen($str) - 1);
}
?echo displayLists(0,3);
?echo displayCategory(13);