如何在PHP中将日期差异作为负数？

Question

I have this code in php to get the difference between two dates. I'm getting the difference but it's always positive. I need the difference to be negative when the final date has passed. I've tried format(), invert, but nothing seems to work.

function dias_transcurridos($fecha_i, $fecha_f)
{
$dias = (strtotime($fecha_i) - strtotime($fecha_f)) / 86400;
$dias = abs($dias);
$dias = floor($dias);
return $dias;
}
$hoy = date('Y-m-d');

Then I call the code in my loop:

$elPlazo =  dias_transcurridos($row["DateEnd"], $hoy);
echo "<td>" . $elPlazo . " Días</td>\n";

How can I get $elPlazo (the difference) as a negative number when the end date has passed today?

Answer 1

The problem is that you have an abs in your code. abs will take the absolute value of any number (ie. remove the negative). Removing the abs will make your function return negative differences.

Answer 2

I would also think about using the built-in PHP DateTime and DateInterval objects because they can handle things like leap days:

<?php

function dias_transcurridos($fecha_i, $fecha_f)
{
    $i = new DateTime($fecha_i);
    $f = new DateTime($fecha_f);

    $interval = $i->diff($f);

    return $interval->days;
}

Answer 3

$today = new DateTime(); $date = new DateTime('2013-03-10');

$interval = $today->diff($date); echo $interval->format("%r%a");