Date Leap Year Validation

function checkDate(date) { //how to use this function since many people recommend this one isLeap = new Date(date, 1, 29).getMonth() == 1; return isLeap; } In ht

Solution 1:

To check if it's leap year :

var isleap = (year % 4 == 0 && (year % 100 != 0 || year % 400 == 0));

to check if the extra day is valid -- is to check how many days were in that month (and if they equal to dd):

32 - new Date(2000, 1, 32).getDate() //1 here is FEB

do if some says : 29 feb 2000

so 32 - new Date(2000, 1, 32).getDate()//29

which is fine . cuz 29==29.

BUT

do if some says : 29 feb 2001

32 - new Date(2001, 1, 32).getDate()//28

and 28!=29 so it's not valid date.