php date 在指定日期內提取出週末和工作日

<?php
  function dump($data)
    {
        $str='<pre style="display: block;padding: 9.5px;margin: 44px 0 0 0;font-size: 
              13px;line-height: 1.42857;color: #333;word-break: break-all;word-wrap: 
              break-word;background-color: #F5F5F5;border: 1px solid #CCC;border-radius: 
              4px;">';

        if(is_bool($data)){
            $show_data = $data?'true':'false';
        }elseif(is_null($data)){
            $show_data = 'null';
        }else{
            $show_data = print_r($data,true);
        }
        $str .=$show_data;
        $str .='</pre>';

        echo $str;
    }
function get_work_day($start_time="2019-11-01",$end_time='2019-11-21')
{
    $start_time = empty($start_time)?time():strtotime($start_time);
	$end_time = empty($end_time)?time():strtotime($end_time)+86400;//最後一天也算
    if($end_time<=$start_time){
    	return array();
    }
    $days = ($end_time - $start_time)/86400;
    $work_day_array = array();//工作日
    $Weekend_day_array = array();//週末
    for ($i=0; $i < $days ; $i++) { 
      $timer = $start_time + 86400*$i;
      $num= date("N",$timer);
      if($num == 6 || $num == 7) {
    	$Weekend_day_array[] = date('Y-m-d',$timer);
      }else{
    	$work_day_array[] = date('Y-m-d',$timer);
    }
   
 }

    return array(
    	'workday'=>$work_day_array,
    	'weekend'=>$Weekend_day_array);
}
$res = get_work_day();
dump($res);exit;