如果你正在使用MySql

function daysSince($date, $date2){
$q = "SELECT DATEDIFF('$date','$date2') AS days;";
$result = execQ($q);
$row = mysql_fetch_array($result,MYSQL_BOTH);
return ($row[0]);

}

function execQ($q){
$result = mysql_query( $q);
if(!$result){echo ('Database error execQ' . mysql_error());echo $q;}    
return $result;

}

你可以试试下面的代码:

$dt1 = strtotime("2019-12-12"); //Enter your first date
$dt2 = strtotime("12-12-2020"); //Enter your second date
echo abs(($dt1 - $dt2) / (60 * 60 * 24));

选择的答案不是最正确的答案，因为它将在UTC之外失败。 根据时区(列表)，可能会有时间调整创建“没有”24小时的日子，这将使计算(60*60*24)失败。

这里有一个例子:

date_default_timezone_set('europe/lisbon');
$time1 = strtotime('2016-03-27');
$time2 = strtotime('2016-03-29');
echo floor( ($time2-$time1) /(60*60*24));
 ^-- the output will be **1**

因此，正确的解决方案是使用DateTime

date_default_timezone_set('europe/lisbon');
$date1 = new DateTime("2016-03-27");
$date2 = new DateTime("2016-03-29");

echo $date2->diff($date1)->format("%a");
 ^-- the output will be **2**

    // Change this to the day in the future
$day = 15;

// Change this to the month in the future
$month = 11;

// Change this to the year in the future
$year = 2012;

// $days is the number of days between now and the date in the future
$days = (int)((mktime (0,0,0,$month,$day,$year) - time(void))/86400);

echo "There are $days days until $day/$month/$year";

<?php
$date1=date_create("2013-03-15");
$date2=date_create("2013-12-12");
$diff=date_diff($date1,$date2);
echo $diff->format("%R%a days");
?>

上面的代码用的很简单。谢谢。

最简单的方法来找出两个日期之间的天数差

$date1 = strtotime("2019-05-25"); 
$date2 = strtotime("2010-06-23");

$date_difference = $date2 - $date1;

$result =  round( $date_difference / (60 * 60 * 24) );

echo $result;