Nodejs Week Calculate toWeekStart(startsFromSunday)

Method Source Code

Date.prototype.toWeekStart = function (startsFromSunday) {
    var dayOfWeek = this.getDay();
    if (startsFromSunday) {
        return this.addDays(-dayOfWeek);
    }// www .jav a  2s  .  c  o m
    if (dayOfWeek == 0) {
        dayOfWeek = 7;
    }
    return this.addDays(1 - dayOfWeek);
};

Related

1. 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;
   };
   

2. offsetByWeek(offset)

   Date.prototype.offsetByWeek = function(offset) {
       this.setTime(this.getTime() + offset * (7 * 24 * 60 * 60 * 1000));
       return this;
   };
   

3. subWeeks(value)

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

4. 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")
   

5. 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);
   ...
   

6. weekNo()

   var firstMonday = new Date(1970, 0, 5).getTime()
   Date.prototype.weekNo = function() {
     var _date = new Date(this)
     _date.setHours(0,0,0,0)
     _date.setDate(_date.getDate() - (_date.getDay() || 7))
     var weekNo = Math.ceil((((_date - firstMonday) / 86400000) + 1) / 7)
     return weekNo
   Date.prototype.weekNoRelative = function() {
   ...
   

7. weekNumber()

   Date.prototype.weekNumber = function() {
      var MaDate = this;
      var mm = MaDate.getMonth(), jj = MaDate.getDate();
      var annee = MaDate.getFullYear();
      var NumSemaine = 0,
      ListeMois = new Array(31,28,31,30,31,30,31,31,30,31,30,31);
      if (annee %4 == 0 && annee %100 !=0 || annee %400 == 0) {ListeMois[1]=29};
      var TotalJour=0;
      for(cpt=0; cpt<mm; cpt++){TotalJour+=ListeMois[cpt];}
   ...
   

8. weekday()

   Date.prototype.weekday = function()
     var days = ["Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"];
     return days[this.getDay()];