PHP计算某时间段内有几个周及某时间为今年第几周

PHP计算某时间段内有几个周及某时间为今年第几周函数

date_default_timezone_set('PRC');
function count_weeks($startDate, $endDate = ''){
  //开始时间
  $startDate = date('Y-m-d', $startDate);
  //结束时间
  if(empty($endDate)) {
    $endDate = date('Y-m-d');
  }else{
    $endDate = date('Y-m-d', $endDate);
  }
  //跨越天数
  $n = (strtotime($endDate)-strtotime($startDate))/86400;
  //判断，跨度小于7天，可能是同一周，也可能是两周
  $endDate = date("Y-m-d",strtotime("$endDate +1 day"));
  if($n=$endDate){        
          $weekList[] =array('s'=>$startDate, 'e'=>date("Y-m-d",strtotime("$endDate -1 day")));
      }else{
          $weekList[] =array('s'=>$startDate, 'e'=>date("Y-m-d",strtotime("$week_end -1 day")));        
          $weekList[] =array('s'=>$week_end, 'e'=>date("Y-m-d",strtotime("$endDate -1 day")));    
      }
  }else{
      //如果跨度大于等于7天，可能是刚好1周或跨2周或跨N周，先找出开始时间 在 那周 的 位置和那周的周末时间
      $day         = date("w",strtotime($startDate))-1;
      $week_start  = date("Y-m-d",strtotime("$startDate -{$day} day"));
      $day         = 7-$day;
      $week_end    = date("Y-m-d",strtotime("$startDate +{$day} day"));
      //先把开始时间那周写入数组
      $weekList[]  =array('s'=>$startDate, 'e'=>date("Y-m-d",strtotime("$week_end -1 day"))); 
      //判断周末是否大于等于结束时间，不管大于(2周)还是等于(1周)，结束时间都是时间段的结束时间。
      if($week_end >= $endDate){
          $weekList[] = array('s'=>$week_end, 'e'=>date("Y-m-d",strtotime("$endDate -1 day")));
      }else{
         //N周的情况用while循环一下，然后写入数组
          while($week_end $start, 'e'=>date("Y-m-d",strtotime("$week_end -1 day")));
              }else{
                  $weekList[]  = array('s'=>$start, 'e'=>date("Y-m-d",strtotime("$endDate -1 day")));
              }
          }
      }
  }
  return $weekList;
}

PHP获取某时间为今年第几周方法

date('W')