获取二维数组某个值的上一级key

    /**
     * @desc 获取二维数组某个键的最大值或最小值
     *
     * @param array $arr
     * @param string $keys
     * @param array $data
     */
    public function phpMaxMin($arr = [],$keys = ''){
        $max['key'] = '';
        $max['value'] = '';
        $min['key'] = '';
        $min['value'] = '';

        foreach ($arr as $key => $val){

            if($max['key'] === ''){

                $max['key'] = $key;
                $max['value'] = $val[$keys];

            }

            if((int)$max['value'] < $val[$keys]){

                $max['key'] = $key;
                $max['value'] = $val[$keys];

            }

            if($min['key'] === ''){

                $min['key'] = $key;
                $min['value'] = $val[$keys];

            }

            if((int)$min['value'] > $val[$keys]){

                $min['key'] = $key;
                $min['value'] = $val[$keys];
            }

        }
        $array['max'] = $max;
        $array['min'] = $min;
        return $array;

    }
    phpMaxMin($array,'key');