Nodejs Year Leap Check isLeapYear()

Method Source Code

/**/*  ww  w .  j av  a2s  .  c  o  m*/
 * Adds the leap year check to the Date prototype
 * @return {Date}
 */

Date.prototype.isLeapYear = function() {
  return Date.isLeapYear(this.getFullYear());
};

Related

1. isLeapYear()

   Date.prototype.isLeapYear = function() {
       var year = this.getFullYear();
       if((year & 3) != 0) return false;
       return ((year % 100) != 0 || (year % 400) == 0);
   };
   Date.prototype.getDOY = function() {
       var dayCount = [0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334];
       var mn = this.getMonth();
       var dn = this.getDate();
   ...
   

2. isLeapYear()

   Date.isLeapYear = function(year) {
       return (((year % 4 === 0) && (year % 100 !== 0)) || (year % 400 === 0)); 
   };
   Date.getDaysInMonth = function(year, month) {
       return [31, (Date.isLeapYear(year) ? 29 : 28), 31, 30, 31, 30, 31, 31, 30, 31, 30, 31][month];
   };
   Date.prototype.isLeapYear = function() {
       return Date.isLeapYear(this.getFullYear()); 
   };
   ...
   

3. isLeapYear()

   Date.prototype.isLeapYear = function(){
     return (0==this.getYear()%4 && ((this.getYear()%100 != 0) || (this.getYear()%400 == 0))); 
   

4. isLeapYear()

   Date.prototype.isLeapYear = function () {
       var year = this.getFullYear();
       return ((year & 3) == 0 && (year % 100 || (year % 400 == 0 && year)));
   

5. isLeapYear()

   Date.prototype.isLeapYear = function () {
     return new Date(this.getFullYear(), 1, 29).getDate() == 29;
   };
   

6. isLeapYear()

   Date.prototype.isLeapYear = function ()
       var y = this.getFullYear();
       return (((y % 4 === 0) && (y % 100 !== 0)) || (y % 400 === 0));
   };
   

7. isLeapYear(year)

   Date.isLeapYear = function(year) {
     return (((year % 4 === 0) && (year % 100 !== 0)) || (year % 400 === 0));
   };
   

8. isLeapYear(year)

   Date.isLeapYear = function (year)
       return (((year % 4 === 0) && (year % 100 !== 0)) || (year % 400 === 0));
   };
   

9. isLeapYear(year)

   function {
     return year%4==0&&(year%100!=0||year%400==0);