Get number of days in a month

nr.days.in.month.php

<?php

function isLeapYear($year)
{
    return $year % 100 == 0
        ? $year % 400 == 0
        : $year % 4 == 0;
}

function getMonthDayCount($year, $month)
{
    switch ($month) {
        case 'april':
        case 'june':
        case 'september':
        case 'november':
            return 30;
        case 'january':
        case 'march':
        case 'may':
        case 'july':
        case 'august':
        case 'october':
        case 'december':
            return 31;
        case 'february':
            return (isLeapYear($year) ? 29 : 28);
        default:
            return 0;
    }
}

var_dump(getMonthDayCount(2017, 'march'));  //prints 31
var_dump(getMonthDayCount(2000, 'february'));   //prints 29
var_dump(getMonthDayCount(1999, 'december'));   //prints 31
var_dump(getMonthDayCount(1600, 'june'));   //prints 30