我在下面的页面上找到了您的文章，其中包含了许多PHP日期时间计算的参考。

使用PHP计算两个日期（和时间）之间的差异。下一页提供了一系列不同的方法（共7种），用于使用PHP执行日期/时间计算，以确定两个日期之间的时间差（小时、弹药）、天、月或年。

请参阅PHP日期时间–计算两个日期之间差值的7种方法。

简单的功能

function time_difference($time_1, $time_2, $limit = null)
{

    $val_1 = new DateTime($time_1);
    $val_2 = new DateTime($time_2);

    $interval = $val_1->diff($val_2);

    $output = array(
        "year" => $interval->y,
        "month" => $interval->m,
        "day" => $interval->d,
        "hour" => $interval->h,
        "minute" => $interval->i,
        "second" => $interval->s
    );

    $return = "";
    foreach ($output AS $key => $value) {

        if ($value == 1)
            $return .= $value . " " . $key . " ";
        elseif ($value >= 1)
            $return .= $value . " " . $key . "s ";

        if ($key == $limit)
            return trim($return);
    }
    return trim($return);
}

像这样使用

回波时间差（$time_1，$time_2，“天”）；

将返回2年8个月2天

我有一些简单的逻辑：

<?php
    per_days_diff('2011-12-12','2011-12-29')
    function per_days_diff($start_date, $end_date) {
        $per_days = 0;
        $noOfWeek = 0;
        $noOfWeekEnd = 0;
        $highSeason=array("7", "8");

        $current_date = strtotime($start_date);
        $current_date += (24 * 3600);
        $end_date = strtotime($end_date);

        $seassion = (in_array(date('m', $current_date), $highSeason))?"2":"1";

        $noOfdays = array('');

        while ($current_date <= $end_date) {
            if ($current_date <= $end_date) {
                $date = date('N', $current_date);
                array_push($noOfdays,$date);
                $current_date = strtotime('+1 day', $current_date);
            }
        }

        $finalDays = array_shift($noOfdays);
        //print_r($noOfdays);
        $weekFirst = array("week"=>array(),"weekEnd"=>array());
        for($i = 0; $i < count($noOfdays); $i++)
        {
            if ($noOfdays[$i] == 1)
            {
                //echo "This is week";
                //echo "<br/>";
                if($noOfdays[$i+6]==7)
                {
                    $noOfWeek++;
                    $i=$i+6;
                }
                else
                {
                    $per_days++;
                }
                //array_push($weekFirst["week"],$day);
            }
            else if($noOfdays[$i]==5)
            {
                //echo "This is weekend";
                //echo "<br/>";
                if($noOfdays[$i+2] ==7)
                {
                    $noOfWeekEnd++;
                    $i = $i+2;
                }
                else
                {
                    $per_days++;
                }
                //echo "After weekend value:- ".$i;
                //echo "<br/>";
            }
            else
            {
                $per_days++;
            }
        }

        /*echo $noOfWeek;
          echo "<br/>";
          echo $noOfWeekEnd;
          echo "<br/>";
          print_r($per_days);
          echo "<br/>";
          print_r($weekFirst);
        */

        $duration = array("weeks"=>$noOfWeek, "weekends"=>$noOfWeekEnd, "perDay"=>$per_days, "seassion"=>$seassion);
        return $duration;
      ?>

前段时间，我编写了一个format_date函数，因为它提供了许多关于日期的选项：

function format_date($date, $type, $seperator="-")
{
    if($date)
    {
        $day = date("j", strtotime($date));
        $month = date("n", strtotime($date));
        $year = date("Y", strtotime($date));
        $hour = date("H", strtotime($date));
        $min = date("i", strtotime($date));
        $sec = date("s", strtotime($date));

        switch($type)
        {
            case 0:  $date = date("Y".$seperator."m".$seperator."d",mktime($hour, $min, $sec, $month, $day, $year)); break;
            case 1:  $date = date("D, F j, Y",mktime($hour, $min, $sec, $month, $day, $year)); break;
            case 2:  $date = date("d".$seperator."m".$seperator."Y",mktime($hour, $min, $sec, $month, $day, $year)); break;
            case 3:  $date = date("d".$seperator."M".$seperator."Y",mktime($hour, $min, $sec, $month, $day, $year)); break;
            case 4:  $date = date("d".$seperator."M".$seperator."Y h:i A",mktime($hour, $min, $sec, $month, $day, $year)); break;
            case 5:  $date = date("m".$seperator."d".$seperator."Y",mktime($hour, $min, $sec, $month, $day, $year)); break;
            case 6:  $date = date("M",mktime($hour, $min, $sec, $month, $day, $year)); break;
            case 7:  $date = date("Y",mktime($hour, $min, $sec, $month, $day, $year)); break;
            case 8:  $date = date("j",mktime($hour, $min, $sec, $month, $day, $year)); break;
            case 9:  $date = date("n",mktime($hour, $min, $sec, $month, $day, $year)); break;
            case 10: 
                     $diff = abs(strtotime($date) - strtotime(date("Y-m-d h:i:s"))); 
                     $years = floor($diff / (365*60*60*24));
                     $months = floor(($diff - $years * 365*60*60*24) / (30*60*60*24));
                     $days = floor(($diff - $years * 365*60*60*24 - $months*30*60*60*24)/ (60*60*24));
                     $date = $years . " years, " . $months . " months, " . $days . "days";
        }
    }
    return($date);
}    

// If you just want to see the year difference then use this function.
// Using the logic I've created you may also create month and day difference
// which I did not provide here so you may have the efforts to use your brain.
// :)
$date1='2009-01-01';
$date2='2010-01-01';
echo getYearDifference ($date1,$date2);
function getYearDifference($date1=strtotime($date1),$date2=strtotime($date2)){
    $year = 0;
    while($date2 > $date1 = strtotime('+1 year', $date1)){
        ++$year;
    }
    return $year;
}

最好的做法是使用PHP的DateTime（和DateInterval）对象。每个日期都封装在DateTime对象中，然后可以在两者之间进行区别：

$first_date = new DateTime("2012-11-30 17:03:30");
$second_date = new DateTime("2012-12-21 00:00:00");

DateTime对象将接受strtotime（）的任何格式。如果需要更具体的日期格式，则可以使用DateTime:：createFromFormat（）创建DateTime对象。

两个对象实例化后，使用DateTime:：diff（）从另一个对象中减去一个对象。

$difference = $first_date->diff($second_date);

$difference现在保存一个包含差异信息的DateInterval对象。var_dump（）如下所示：

object(DateInterval)
  public 'y' => int 0
  public 'm' => int 0
  public 'd' => int 20
  public 'h' => int 6
  public 'i' => int 56
  public 's' => int 30
  public 'invert' => int 0
  public 'days' => int 20

要格式化DateInterval对象，我们需要检查每个值，如果值为0，则将其排除：

/**
 * Format an interval to show all existing components.
 * If the interval doesn't have a time component (years, months, etc)
 * That component won't be displayed.
 *
 * @param DateInterval $interval The interval
 *
 * @return string Formatted interval string.
 */
function format_interval(DateInterval $interval) {
    $result = "";
    if ($interval->y) { $result .= $interval->format("%y years "); }
    if ($interval->m) { $result .= $interval->format("%m months "); }
    if ($interval->d) { $result .= $interval->format("%d days "); }
    if ($interval->h) { $result .= $interval->format("%h hours "); }
    if ($interval->i) { $result .= $interval->format("%i minutes "); }
    if ($interval->s) { $result .= $interval->format("%s seconds "); }

    return $result;
}

现在剩下的就是调用$differenceDateInterval对象上的函数：

echo format_interval($difference);

我们得到了正确的结果：

20天6小时56分30秒

用于实现目标的完整代码：

/**
 * Format an interval to show all existing components.
 * If the interval doesn't have a time component (years, months, etc)
 * That component won't be displayed.
 *
 * @param DateInterval $interval The interval
 *
 * @return string Formatted interval string.
 */
function format_interval(DateInterval $interval) {
    $result = "";
    if ($interval->y) { $result .= $interval->format("%y years "); }
    if ($interval->m) { $result .= $interval->format("%m months "); }
    if ($interval->d) { $result .= $interval->format("%d days "); }
    if ($interval->h) { $result .= $interval->format("%h hours "); }
    if ($interval->i) { $result .= $interval->format("%i minutes "); }
    if ($interval->s) { $result .= $interval->format("%s seconds "); }

    return $result;
}

$first_date = new DateTime("2012-11-30 17:03:30");
$second_date = new DateTime("2012-12-21 00:00:00");

$difference = $first_date->diff($second_date);

echo format_interval($difference);