php 无限分类

<?php
    function genTree($items,$id='id',$pid='pid',$son = 'children'){
        $tree = array();
        $tmpMap = array();  

        foreach ($items as $item) {
            $tmpMap[$item[$id]] = $item;
        }  

        foreach ($items as $key => $item) {
            if (isset($tmpMap[$item[$pid]])) {
                $tmpMap[$item[$pid]][$son][$key] = &$tmpMap[$key];
            } else {
                $tree[] = &$tmpMap[$item[$id]];
            }
        }
        unset($tmpMap);
        return $tree;
    }  

    $items1 = array(
            array('id' => 1,  'pid' => 0,  'name' => '一级' ),
            array('id' => 11, 'pid' => 0,  'name' => '一级' ),
            array('id' => 2,  'pid' => 1,  'name' => '二级' ),
            array('id' => 10, 'pid' => 11, 'name' => '二级' ),
            array('id' => 3,  'pid' => 1,  'name' => '二级' ),
            array('id' => 12, 'pid' => 11, 'name' => '二级' ),
            array('id' => 9,  'pid' => 1,  'name' => '二级' ),
            array('id' => 14, 'pid' => 1,  'name' => '二级' ),
            array('id' => 4,  'pid' => 9,  'name' => '三级' ),
            array('id' => 6,  'pid' => 9,  'name' => '三级' ),
            array('id' => 7,  'pid' => 4,  'name' => '四级' ),
            array('id' => 8,  'pid' => 4,  'name' => '四级' ),
            array('id' => 5,  'pid' => 4,  'name' => '四级' ),
            array('id' => 13, 'pid' => 4,  'name' => '四级' ),
            array('id' => 15, 'pid' => 8,  'name' => '五级' ),
            array('id' => 16, 'pid' => 8,  'name' => '五级' ),
            array('id' => 17, 'pid' => 8,  'name' => '五级' ),
            array('id' => 18, 'pid' => 16, 'name' => '六级' ),
    );
    echo "<pre>";
    echo "父节点:<br/>";
    print_r(genTree($items1));

　　

<?php
    header("Content-type:text/html;charSet=utf8");
    /**
     * 创建父节点树形数组
     * 参数
     * $ar 数组，邻接列表方式组织的数据
     * $id 数组中作为主键的下标或关联键名
     * $pid 数组中作为父键的下标或关联键名
     * 返回 多维数组
     **/
    function find_parent($ar, $id='id', $pid='pid') {
        foreach($ar as $v) $t[$v[$id]] = $v;
        foreach ($t as $k => $item){
            if( $item[$pid] ){
            if( ! isset($t[$item[$pid]]['parent'][$item[$pid]]) )
                $t[$item[$id]]['parent'][$item[$pid]] = &$t[$item[$pid]];
            }
        }
        return $t;
    }  

    /**
     * 创建子节点树形数组
     * 参数
     * $ar 数组，邻接列表方式组织的数据
     * $id 数组中作为主键的下标或关联键名
     * $pid 数组中作为父键的下标或关联键名
     * 返回 多维数组
     **/
    function find_child($ar, $id='id', $pid='pid') {
        foreach($ar as $v) $t[$v[$id]] = $v;
        foreach ($t as $k => $item){
            if( $item[$pid] ) {
                $t[$item[$pid]]['child'][$item[$id]] = &$t[$k];
            }
        }
        return $t;
    }  

    $data = array(
      array('ID'=>1, 'PARENT'=>0, 'NAME'=>'祖父'),
      array('ID'=>2, 'PARENT'=>1, 'NAME'=>'父亲'),
      array('ID'=>3, 'PARENT'=>1, 'NAME'=>'叔伯'),
      array('ID'=>4, 'PARENT'=>2, 'NAME'=>'自己'),
      array('ID'=>5, 'PARENT'=>4, 'NAME'=>'儿子'),
    );  

    $p = find_parent($data, 'ID', 'PARENT');
    $c = find_child($data, 'ID', 'PARENT');
    echo "<pre>";
    echo "父节点:<br/>";
    print_r($p);
    echo "子节点:<br/>";
    print_r($c);