PHP基于变量的引用实现的树状结构

直接上代码：

function aryTree($ary, $tagId = 'id', $tagPid = 'pid', $tagSub = '_sub') {
    
    if(is_array($ary)) {
        
        $refer = array(); // 创建基于主键(id)的数组引用(映射)

        foreach ($ary as $k => $v) {
            $refer[$v[$tagId]] =& $ary[$k]; // "引用":不同的变量名访问同一个内容
        }

        foreach ($ary as $k => $v) {
            if (isset($refer[$v[$tagPid]])) {
                $parent =& $refer[$v[$tagPid]];
                $parent[$tagSub][$v[$tagId]] =& $ary[$k];
                unset($ary[$k]);
            }
        }
        unset($refer);
    }

    return $ary;
}

以下Function是可设置父级级别的代码：

function aryTree($ary, $id = 'id', $pid = 'pid', $sub = '_sub', $root = 0) {

    $tree = array();

    if(is_array($ary)) {
        
        $refer = array();

        foreach ($ary as $k => $v) {
            $refer[$v[$id]] =& $ary[$k];
        }

        foreach ($ary as $k => $v) {
            
            $parentId =  $v[$pid];

            if ($root == $parentId) {

                $tree[$v[$id]] =& $ary[$k];

            }else{

                if (isset($refer[$parentId])) {
                    $parent =& $refer[$parentId];
                    $parent[$sub][$v[$id]] =& $ary[$k];
            　　　　 unset($ary[$k]);
                }
            }
        }
        unset($refer, $ary);
    }

    return $tree;
}