PHP 无限递归函数

/**
 * 无限递归下拉选择框
 * @param $data   数组
 * @param $pid    父id
 * @param int $t  循环次数：作用缩进
 * @param int $selected 选中的下标
 * @return string
 * @author zhengjingqiang
 * @email scenewood@163.com
 * @date 2015-10-22
 */
function html_options($data=array(), $pid=0, $t=-1, $selected=0){
    $html_options = '';
    $t++;
    $nbspstr = str_repeat(' ', $t * 4);
    if ($data) {
        foreach ($data as $k => $v) {
            if($pid == $v['pid']){
                // 判断是否是最后一个下拉选项卡
                $symbol_str = (count($data) == ($k+1)) ? '┗' : '┣';
                // 判断是否选中
                $selected_str = ($selected == $v['id']) ? ' selected="selected"' : '';
                // 下拉选择框数据
                $html_options .= '<option value="' . $v['id'] . '" '.$selected_str.'>' . $nbspstr . $symbol_str . $v['name'] . '</option>';
                // 无限循环查找子集
                $html_options .= html_options($data, $v['id'], $t, $selected);
            }
        }
    }
    return $html_options;
}

/**
 * 二维数组递归
 * @param array $arr
 * @return array
 * @author zhengjingqiang
 * @email scenewood@163.com
 */
function category($arr = array()){
    $info = array();
    if(count($arr) > 0){
        foreach($arr as $k => $vo){
            if($vo['pid'] == 0 ){
                foreach($arr as $v){
                    if($v['pid'] == $vo['id']){
                        $vo['children'][] = $v;
                    }
                }
                $info[] = $vo;
            }
        }
    }
    return $info;
}

/**
 * 无限分类
 * @param $array
 * @param int $pid
 * @return array
 * @author zhengjingqiang
 * @email scenewood@163.com
 */
function menuTree($array,$pid){
    $arr = array();
    foreach ($array as $v) {
        if ($v['pid'] == $pid) {
            $tem = menuTree($array, $v['id']);
            //判断是否存在子数组
            $tem && $v['child'] = $tem;
            $arr[] = $v;
        }
    }
    return $arr;
}