Nodejs Week Calculate offsetByWeek(offset)

Method Source Code

Date.prototype.offsetByWeek = function(offset) {
    this.setTime(this.getTime() + offset * (7 * 24 * 60 * 60 * 1000));
    return this;/*from w w  w .  j  a  v  a2s. co  m*/
};

Related

1. getFullWeek()

   Date.prototype.getFullWeek = function(){
       var jan1, w, d = new Date(this);
       d.setDate(d.getDate()+4-(d.getDay()||7));   
       jan1 = new Date(d.getFullYear(),0,1);       
       w = Math.ceil((((d-jan1)/86400000)+1)/7);   
       return {y: d.getFullYear(), w: w };
   };
   Date.prototype.getWeek = function(){ return this.getFullWeek().w; };
   var getWeeksInYear = function(y){ return new Date(y,11,28).getFullWeek().w; };
   ...
   

2. getRealWeek()

   Date.prototype.getRealWeek = function()
       var monday = this;
       if (monday.getDay() < 1) {
           monday = monday.clone().next().monday();
       return monday.getWeek();
   };
   

3. getStudyWeek()

   Date.prototype.getStudyWeek = function () {
     var inc = (this.getDay() == 6) ? 1 : 0;
     return this.getWeek() + inc;
   };
   

4. moveToBeginOfWeek(weekStart)

   Date.prototype.moveToBeginOfWeek = function(weekStart)
       if (this.getDay() != weekStart) {
           this.moveToDayOfWeek(weekStart, -1);
       return this;
   };
   

5. moveToEndOfWeek(weekStart)

   Date.prototype.moveToEndOfWeek = function(weekStart)
       var weekEndDay = weekStart + 6;
       if (weekEndDay > 6) {
           weekEndDay -= 7;
       if (this.getDay() != weekEndDay) {
           this.moveToDayOfWeek(weekEndDay, 1);
       return this;
   };
   

6. subWeeks(value)

   Date.prototype.subWeeks = function(value) {
     this.subDays(value * 7);
     return this;
   };
   

7. toWeekDays()

   Date.prototype.toWeekDays = function () {
     var weekday = this.clone()
     if (!weekday.is().sunday()) {
       weekday.sunday().add(-7).days()
     var week = [weekday.clone()]
     for (var day = 0; day < 6; day++) {
       week.push(weekday.add(1).days().clone())
     return week
   Date.prototype.toNextWeekDays = function () {
     return this.add(7).days().toWeekDays()
   Date.prototype.toPreviousWeekDays = function () {
     return this.add(-7).days().toWeekDays()
   Date.prototype.compare = function (date) {
     var year = this.getYear() - date.getYear()
     if (year > 0)
       return "In " + year + " Years"
     else if (year < 0)
       return -year + " Years Ago"
     else {
       var month = this.getMonth() - date.getMonth()
       if (month > 0)
         return "In " + month + " Months"
       else if (month < 0)
         return -month + " Months Ago"
       else {
         var week = this.getWeekOfYear() - date.getWeekOfYear()
         if (week > 0)
           return "In " + week + " Weeks"
         else if (week < 0)
           return -week + " Weeks Ago"
         else {
           if (this.getDay() - date.getDay() == 0)
             return "Today"
           else
             return this.toString("dddd")
   

8. toWeekEnd(startsFromSunday)

   Date.prototype.toWeekEnd = function (startsFromSunday) {
       var dayOfWeek = this.getDay();
       if (startsFromSunday) {
           return this.addDays(6 - dayOfWeek);
       if (dayOfWeek == 0) {
           dayOfWeek = 7;
       return this.addDays(7 - dayOfWeek);
   ...
   

9. toWeekStart(startsFromSunday)

   Date.prototype.toWeekStart = function (startsFromSunday) {
       var dayOfWeek = this.getDay();
       if (startsFromSunday) {
           return this.addDays(-dayOfWeek);
       if (dayOfWeek == 0) {
           dayOfWeek = 7;
       return this.addDays(1 - dayOfWeek);
   ...