php 无限级分类，超级简单的无限级分类，支持输

<?php error_reporting(E_ALL ^ E_NOTICE); class Tree { /** +------------------------------------------------ * 生成树型结构所需要的2维数组 +------------------------------------------------ * @author abc +------------------------------------------------ * @var Array */ var $arr = array(); /** +------------------------------------------------ * 生成树型结构所需修饰符号，可以换成图片 +------------------------------------------------ * @author abc +------------------------------------------------ * @var Array */ var $icon = array(' │',' ├',' └'); /** * @access private */ var $ret = ''; /** * 构造函数，初始化类 * @param array 2维数组，例如： * array( * 1 => array('id'=>'1','parentid'=>0,'name'=>'一级栏目一'), * 2 => array('id'=>'2','parentid'=>0,'name'=>'一级栏目二'), * 3 => array('id'=>'3','parentid'=>1,'name'=>'二级栏目一'), * 4 => array('id'=>'4','parentid'=>1,'name'=>'二级栏目二'), * 5 => array('id'=>'5','parentid'=>2,'name'=>'二级栏目三'), * 6 => array('id'=>'6','parentid'=>3,'name'=>'三级栏目一'), * 7 => array('id'=>'7','parentid'=>3,'name'=>'三级栏目二') * ) */ function tree($arr=array()) { $this->arr = $arr; $this->ret = ''; return is_array($arr); } /** * 得到父级数组 * @param int * @return array */ function get_parent($myid) { $newarr = array(); if(!isset($this->arr[$myid])) return false; $pid = $this->arr[$myid]['parentid']; $pid = $this->arr[$pid]['parentid']; if(is_array($this->arr)) { foreach($this->arr as $id => $a) { if($a['parentid'] == $pid) $newarr[$id] = $a; } } return $newarr; } /** * 得到子级数组 * @param int * @return array */ function get_child($myid) { $a = $newarr = array(); if(is_array($this->arr)) { foreach($this->arr as $id => $a) { if($a['parentid'] == $myid) $newarr[$id] = $a; } } return $newarr ? $newarr : false; } /** * 得到当前位置数组 * @param int * @return array */ function get_pos($myid,&$newarr) { $a = array(); if(!isset($this->arr[$myid])) return false; $newarr[] = $this->arr[$myid]; $pid = $this->arr[$myid]['parentid']; if(isset($this->arr[$pid])) { $this->get_pos($pid,$newarr); } if(is_array($newarr)) { krsort($newarr); foreach($newarr as $v) { $a[$v['id']] = $v; } } return $a; } /** * ------------------------------------- * 得到树型结构 * ------------------------------------- * @author abc * @param $myid 表示获得这个ID下的所有子级 * @param $str 生成树形结构基本代码, 例如: "<option value=\$id \$select>\$spacer\$name</option>" * @param $sid 被选中的ID, 比如在做树形下拉框的时候需要用到 * @param $adds * @param $str_group */ function get_tree($myid, $str, $sid = 0, $adds = '', $str_group = '') { $number=1; $child = $this->get_child($myid); if(is_array($child)) { $total = count($child); foreach($child as $id=>$a) { $j=$k=''; if($number==$total) { $j .= $this->icon[2]; } else { $j .= $this->icon[1]; $k = $adds ? $this->icon[0] : ''; } $spacer = $adds ? $adds.$j : ''; $selected = $id==$sid ? 'selected' : ''; @extract($a); $parentid == 0 && $str_group ? eval("\$nstr = \"$str_group\";") : eval("\$nstr = \"$str\";"); $this->ret .= $nstr; $this->get_tree($id, $str, $sid, $adds.$k.'&nbsp;',$str_group); $number++; } } return $this->ret; } /** * 同上一方法类似,但允许多选 */ function get_tree_multi($myid, $str, $sid = 0, $adds = '') { $number=1; $child = $this->get_child($myid); if(is_array($child)) { $total = count($child); foreach($child as $id=>$a) { $j=$k=''; if($number==$total) { $j .= $this->icon[2]; } else { $j .= $this->icon[1]; $k = $adds ? $this->icon[0] : ''; } $spacer = $adds ? $adds.$j : ''; $selected = $this->have($sid,$id) ? 'selected' : ''; @extract($a); eval("\$nstr = \"$str\";"); $this->ret .= $nstr; $this->get_tree_multi($id, $str, $sid, $adds.$k.'&nbsp;'); $number++; } } return $this->ret; } function have($list,$item){ return(strpos(',,'.$list.',',','.$item.',')); } /** +------------------------------------------------ * 格式化数组 +------------------------------------------------ * @author abc +------------------------------------------------ */ function getArray($myid=0, $sid=0, $adds='') { $number=1; $child = $this->get_child($myid); if(is_array($child)) { $total = count($child); foreach($child as $id=>$a) { $j=$k=''; if($number==$total) { $j .= $this->icon[2]; } else { $j .= $this->icon[1]; $k = $adds ? $this->icon[0] : ''; } $spacer = $adds ? $adds.$j : ''; @extract($a); $a['name'] = $spacer.' '.$a['name']; $this->ret[$a['id']] = $a; $fd = $adds.$k.'&nbsp;'; $this->getArray($id, $sid, $fd); $number++; } } return $this->ret; } } $data=array( 1 => array('id'=>'1','parentid'=>0,'name'=>'一级栏目一'), 2 => array('id'=>'2','parentid'=>0,'name'=>'一级栏目二'), 3 => array('id'=>'3','parentid'=>1,'name'=>'二级栏目一'), 4 => array('id'=>'4','parentid'=>1,'name'=>'二级栏目二'), 5 => array('id'=>'5','parentid'=>2,'name'=>'二级栏目三'), 6 => array('id'=>'6','parentid'=>3,'name'=>'三级栏目一'), 7 => array('id'=>'7','parentid'=>3,'name'=>''), 8 => array('id'=>'8','parentid'=>3,'name'=>'三级栏目三'), 9 => array('id'=>'9','parentid'=>7,'name'=>'四级分类三'), ); $tree = new Tree; $tree->tree($data); // 如果使用数组, 请使用 getArray方法 //$tree->getArray(); // 下拉菜单选项使用 get_tree方法 $html='<select>'; $str = "<option value=\$id \$select>\$spacer\$name</option>"; $html .= $tree->get_tree(0,$str,-1).'</select>'; echo $html; ?>