php - 错误 : Call to a member function format() on a non-object Generating Each Day of Year

Question

我有一个日历类，我只从用户输入年份并生成一年中的所有天数并保存在数据库中。

class Calendar
{
   /**
     * @var \DateTime
     *
     * @ORM\Column(name="today_date", type="datetime", nullable=true)
     */
    protected $todayDate;
    /**
     * @var boolean $isBusinessDay
     * @ORM\Column(name="is_business_day", type="boolean", nullable=true)
     */
    protected $isBusinessDay;
    /**
     * @var boolean $isHoliday
     * @ORM\Column(name="is_holiday", type="boolean", nullable=true)
     */
    protected $isHoliday;
    /**
     * @var time $openTime
     *
     * @ORM\Column(name="open_time", type="time", nullable=true)
     */
    protected $openTime;
    /**
     * @var time $openTime
     *
     * @ORM\Column(name="close_time", type="time", nullable=true)
     */
    protected $closeTime;

}

if ($form->isSubmitted() && $form->isValid()) { 
  $weekday = $form["weekday"]->getData();
  $start_date = $form["todayDate"]->getData();
  $start_date = (string) $start_date->format('Y-m-d');
  $start_day = date('z', strtotime($start_date));
  $days_in_a_year = date('z', strtotime('2016-12-31'));  
  $number_of_days = ($days_in_a_year - $start_day) +1 ;
  for ($i = 0; $i < $number_of_days; $i++) {
      $date = strtotime(date("Y-m-d", strtotime($start_date)) . " +$i day");
      print date('d F - l', $date) .'<br />';
      if (in_array(date('l', $date), $weekday))
      {
        print "Match found".'<br />';
        $date_temp2 = date('Y-m-d',$date);
        print $date_temp2.'<br />';
        $date_temp = new \DateTime($date_temp2);
        $TodayDate = $date_temp->format('Y-m-d');
        $calendar2 = new Calendar();
        $calendar2->setTodayDate($TodayDate);
        $calendar2->setOpenTime($form["openTime"]->getData());
        $calendar2->setCloseTime($form["closeTime"]->getData());
        $calendar2->setIsBusinessDay(true);
        $calendar2->setIsHoliday(false);
        $em->persist($calendar2);
      }
      else
      {
        print "Match not found".'<br />';
        $calendar2 = new Calendar();
        $calendar2->setIsBusinessDay(false);
        $calendar2->setIsHoliday(true);
        $em->persist($calendar2);
       }
      }
    $em->flush(); 
   }

实际上我只想从用户那里得到年份。获取一年中的第一天并添加一个增量日存储在数据库中。 在 If Block 中，它打印整年的日期。到

30 December - Friday
Match found
2016-12-30
31 December - Saturday
Match not found

最后我得到了这个错误

Error: Call to a member function format() on a non-object

Answer 1

来自 $form['todayDate'] 的 $start_date 肯定是 null。

添加检查以防止此错误。

改变:

$start_date = $form['todayDate'];

收件人:

$start_date = $form['todayDate'] ?: new \DateTime();

像这样，您将当前日期作为 DateTime 对象获取并可以使用 format('Y-m-d') 。