Nodejs Week Get getWeekOfYear()

Method Source Code

/** First week of the year is 0 */
Date.prototype.getWeekOfYear = function() {
   var d = new Date(+this);
   d.setHours(0,0,0);//ww  w  .  j  av  a2 s . co  m
   d.setDate(d.getDate()+4-(d.getDay()||7));
   return Math.ceil((((d-new Date(d.getFullYear(),0,1))/8.64e7))/7);
};

Related

1. getWeekNumber()

   Date.prototype.getWeekNumber = function() {
       var target = new Date(this.valueOf());
       var dauNumber = (this.getDay() + 6) % 7;
       target.setDate(target.getDate() - dauNumber + 3);
       var jan4 = new Date(target.getFullYear(), 0, 4);
       var dayDiff = (target - jan4) / 86400000;
       if (new Date(target.getFullYear(), 0, 1).getDay() < 5) {
           return 1 + Math.ceil(dayDiff / 7);
       else {
           return Math.ceil(dayDiff / 7);
   

2. getWeekNumber()

   Date.prototype.getWeekNumber = function(){
       var d = new Date(+this);
       d.setHours(0,0,0);
       d.setDate(d.getDate()+4-(d.getDay()||7));
       return Math.ceil((((d-new Date(d.getFullYear(),0,1))/8.64e7)+1)/7);
   };
   

3. getWeekNumber()

   Date.prototype.getWeekNumber = function () {
       var d = new Date(+this);
       d.setHours(0, 0, 0, 0);
       d.setDate(d.getDate() + 4 - (d.getDay() || 7));
       return Math.ceil((((d - new Date(d.getFullYear(), 0, 1)) / 8.64e7) + 1) / 7);
   };
   

4. getWeekNumber()

   Date.prototype.getWeekNumber = function () {
     var d = new Date(this);
     d.setHours(0, 0, 0);
     d.setDate(d.getDate() + 4 - (d.getDay() || 7));
     return Math.ceil((((d - new Date(d.getFullYear(), 0, 1)) / 8.64e7) + 1) / 7);
   };
   

5. getWeekOfMonth()

   Date.prototype.getWeekOfMonth = function () {
     var today = new Date(this.getFullYear(), this.getMonth(), this.getDate());
     var firstOfMonth = new Date(today.getFullYear(), today.getMonth(), 1);
     return Math.ceil((((today - firstOfMonth) / 86400000) + firstOfMonth.getDay() + 1) / 7);
   };
   

6. getWeekOfYear()

   Date.prototype.getWeekOfYear = function () {
       var now = this.getDayOfYear() + (4 - this.getDay());
       var jan1 = new Date(this.getFullYear(), 0, 1);
       var then = (7 - jan1.getDay() + 4);
       document.write(then);
       return String.leftPad(((now - then) / 7) + 1, 2, "0");
   

7. getWeekOfYear()

   Date.prototype.getWeekOfYear = function () {
     var today = new Date(this.getFullYear(), this.getMonth(), this.getDate());
     var firstOfYear = new Date(today.getFullYear(), 0, 1);
     return Math.ceil((((today - firstOfYear) / 86400000) + firstOfYear.getDay() + 1) / 7);
   };