每个月的第一天

Question

如果我从当前日期开始,我怎样才能获得每个月的第一个星期五？

我正在考虑使用$ date-> get(Zend :: WEEKDAY)并将其与星期五进行比较,然后与DAY进行比较并检查它是否小于或等于7.然后在其上添加1个月.

必须有更简单的东西？

Answer 1

怎么样

$firstFridayOfOcober = strtotime('first friday of october');

或者把它变成一个方便的功能: -

 /**
 * Returns a timestamp for the first friday of the given month
 * @param string $month
 * @return type int
 */
function firstFriday($month)
{
    return strtotime("first friday of $month");
}

您可以像Zend_Date一样使用它: -

$zDate = new Zend_Date();
$zDate->setTimestamp(firstFriday('october'));

然后Zend_Debug::dump($zDate->toString());会产生: -

string '7 Oct 2011 00:00:00' (length=19)

我会说这简单得多:)

经过多次思考后编辑:

一个更通用的功能对你来说可能更有用,所以我建议使用它: -

/**
 * Returns a Zend_Date object set to the first occurence
 * of $day in the given $month.
 * @param string $day
 * @param string $month
 * @param optional mixed $year can be int or string
 * @return type Zend_Date
 */
function firstDay($day, $month, $year = null)
{
    $zDate = new Zend_Date();
    $zDate->setTimestamp(strtotime("first $day of $month $year"));
    return $zDate;
}

这些天我首选的方法是扩展PHP的DateTime对象: -

class MyDateTime extends DateTime
{
    /**
    * Returns a MyDateTime object set to 00:00 hours on the first day of the month
    * 
    * @param string $day Name of day
    * @param mixed $month Month number or name optional defaults to current month
    * @param mixed $year optional defaults to current year
    * 
    * @return MyDateTime set to last day of month
    */
    public function firstDayOfMonth($day, $month = null, $year = null)
    {
        $timestr = "first $day";
        if(!$month) $month = $this->format('M');
        $timestr .= " of $month $year";
        $this->setTimestamp(strtotime($timestr));
        $this->setTime(0, 0, 0);
        var_dump($this);
    }
}
$dateTime = new MyDateTime();
$dateTime->firstDayOfMonth('Sun', 'Jul', 2011);

得到: -

object(MyDateTime)[36]
  public 'date' => string '2011-07-03 00:00:00' (length=19)
  public 'timezone_type' => int 3
  public 'timezone' => string 'UTC' (length=3)