get between two date all days for every Month in PHP

Question

How i can to get all days for every Month between two days in array like this

$dateStart = "2016/12/14"; 
$dateFin =   "2017/04/21"

[2016/12/14 - 2016/12/31] => 17 days
[2017/01/01 - 2017/01/31] => 31 days
[2017/02/01 - 2017/02/28] => 28 days
[2017/03/01 - 2017/03/30] => 31 days
[2017/04/01 - 2017/04/21] => 21 days

Answer 1

You can use the function cal_days_in_month plus DateTime class:

<?php
$dateStart = new DateTime("2016/12/14");
$dateFin = new DateTime("2017/04/21");
$firstDay = $dateStart->format('Y/m/d');
$lastDay = $dateStart->format('Y/m/t');
$totalMonths = $dateStart->diff($dateFin)->m + ($dateStart->diff($dateFin)->y*12);
$result = [];
for ($i = 0; $i <= $totalMonths; $i++)
{
    if ($i != 0){
        $dateStart->modify('first day of next month');
        $firstDay = $dateStart->format('Y/m/d');
        $dateStart->modify('last day of month');
        $lastDay = $dateStart->format('Y/m/t');
    }

    $nextDate = explode('/', $firstDay);

    $totalDays = cal_days_in_month(CAL_GREGORIAN, $nextDate[1], $nextDate[2]);
    if ($i == 0){
        $totalDays -= $dateStart->format('d');
    } else if ($i == $totalMonths) {
        $totalDays = $dateFin->format('d');
    }

    $result["$firstDay - $lastDay"] = $totalDays;
}

var_dump($result);

Lacks improvement, but gives what you asked.

Routine Improved, check below:

$dateStart = new DateTime("2016/12/14");
$dateFin = new DateTime("2017/04/21");
$totalMonths = $dateStart->diff($dateFin)->m + ($dateStart->diff($dateFin)->y*12);
$result = [];
for ($i = 0; $i <= $totalMonths; $i++)
{
    if ($i != 0){
        $obj = $dateStart->modify('first day of next month');
    }

    $firstDay = $dateStart->format('Y/m/d');
    if ($i == $totalMonths){
        $lastDay = $dateFin->format('Y/m/d');
    } else {
        $lastDay = $dateStart->format('Y/m/t');
    }
    $firstDayObj = strtotime($firstDay);
    $lastDayObj = strtotime($lastDay);
    $totalDays = (int) ceil(($lastDayObj - $firstDayObj) / 86400);
    $totalDays = ((int) $dateStart->format('d') == 1) ? $totalDays + 1 : $totalDays;
    $result["$firstDay - $lastDay"] = $totalDays;
}

var_dump($result);

//array(5) { ["2016/12/14 - 2016/12/31"]=> int(17) ["2017/01/01 - 2017/01/31"]=> int(31) ["2017/02/01 - 2017/02/28"]=> int(28) ["2017/03/01 - 2017/03/31"]=> int(31) ["2017/04/01 - 2017/04/21"]=> int(21) }