Get number days in a specified month using javascript - Количество дней в месяце

js-daysInMonth.js

function daysInMonth(month,year) {
    return new Date(year, month, 0).getDate();
}

//July
daysInMonth(7,2009); //31
//February
daysInMonth(2,2009); //28
daysInMonth(2,2008); //29