php 获取上一周下一周的日期列表

    /**
     * 获取某天的一周日期
     * @date    2021-01-08
     * @version 1.0
     * @param   string     $time   [日期]
     * @param   string     $format [日期格式]
     * @return  [type]             [description]
     */
   function get_week($time = '', $format = 'Y-m-d')
    {
        $time = $time != '' ? $time : time();
        //获取当前周几
        $week     = date('w', $time);
        $weekname = array('星期一', '星期二', '星期三', '星期四', '星期五', '星期六', '星期日');
        //星期日排到末位
        if (empty($week)) {
            $week = 7;
        }
        $date = [];
        for ($i = 0; $i < 7; $i++) {
            $date_time = date($format, strtotime('+' . $i + 1 - $week . ' days', $time));
            $item      = [
                'date' => $date_time,
                'week' => $weekname[$i],
            ];
            $date[$date_time] = $item;
        }
        return $date;
    }


  $page      = (int) $page; ##页码本页0，上一页page-1，下一页page+1;
  $daytime   = strtotime(date("Y-m-d", strtotime("+$page week", time())));
  $week_list = get_week($daytime);
  echo "<pre>";print_r($week_list);die();

##输出

Array
(
    [2020-12-21] => Array
        (
            [date] => 2020-12-21
            [week] => 星期一
        )

    [2020-12-22] => Array
        (
            [date] => 2020-12-22
            [week] => 星期二
        )

    [2020-12-23] => Array
        (
            [date] => 2020-12-23
            [week] => 星期三
        )

    [2020-12-24] => Array
        (
            [date] => 2020-12-24
            [week] => 星期四
        )

    [2020-12-25] => Array
        (
            [date] => 2020-12-25
            [week] => 星期五
        )

    [2020-12-26] => Array
        (
            [date] => 2020-12-26
            [week] => 星期六
        )

    [2020-12-27] => Array
        (
            [date] => 2020-12-27
            [week] => 星期日
        )

)