Sort an array of dates using usort() and sort() functions by the timestamp converted by mktime()

Question

I have an array of dates and I have to sort it by using the described functions.

Here is what I have:

$dates = array (\'10-10-2003\', \'2-17-2002\', \'2-         


        

Answer 1

Here's an alternate solution for you.

<?php
$dates = array(
    '10-10-2003',
    '2-17-2002',
    '2-16-2003',
    '1-01-2005',
    '10-10-2004',
);

function toTime($date) {
    list($month, $day, $year) = explode('-', $date);
    return mktime(0, 0, 0, $month, $day, $year);
}

function sortByTime($a, $b) {
    $a = toTime($a);
    $b = toTime($b);
    if($a == $b) {
        return 0;
    }
    return $a < $b ? -1 : 1 ;
}

usort($dates, 'sortByTime');

print_r($dates);

/*
    Array
    (
        [0] => 2-17-2002
        [1] => 2-16-2003
        [2] => 10-10-2003
        [3] => 10-10-2004
        [4] => 1-01-2005
    )
*/

Answer 2

In your date_tim_timestamp function, you are essentially throwing away your date in place of the integer value.

Try this instead:

function date_to_timestamp($d){
    $newarr = array();
    foreach($d as $f) {
        $arr=explode("-",$f);
        //array_push($newarr, mktime(0,0,0,$arr[0],$arr[1],$arr[2]));
        $int_version = mktime(0,0,0,$arr[0],$arr[1],$arr[2]);
        $newarr[$int_version] = $f;
    }
    return $newarr;
}

Using this approach, you wont need to use usort(), just ksort()