JavaScript date calculation with months difference

Question

I want to calculate a new date by adding a number of months to a specific date.

For example:

I have a date "06/30/2012" (30th June 2012), and a number of months "2" or "3" months.

Now I want a function which gets both values and returns a date which is 2 months after the specified date.

Please show me how this can be achieved.

Some one answer it here already, you should search first http://stackoverflow.com/questions/7763327/how-to-calculate-date-difference-in-javascript — James, Jun 29 '12 at 06:52
Possible duplicate http://stackoverflow.com/questions/5645058/how-to-add-months-in-javascript-date — bart s, Jun 29 '12 at 06:54

score 1 · Accepted Answer · answered Jun 29 '12 at 06:55

You can try putting this code, Which has everything you need with date Addition/Subtraction

Date.prototype.add = function (sInterval, iNum){
      var dTemp = this;
      if (!sInterval || iNum == 0) return dTemp;
      switch (sInterval.toLowerCase()){
        case "ms":
          dTemp.setMilliseconds(dTemp.getMilliseconds() + iNum);
          break;
        case "s":
          dTemp.setSeconds(dTemp.getSeconds() + iNum);
          break;
        case "mi":
          dTemp.setMinutes(dTemp.getMinutes() + iNum);
          break;
        case "h":
          dTemp.setHours(dTemp.getHours() + iNum);
          break;
        case "d":
          dTemp.setDate(dTemp.getDate() + iNum);
          break;
        case "mo":
          dTemp.setMonth(dTemp.getMonth() + iNum);
          break;
        case "y":
          dTemp.setFullYear(dTemp.getFullYear() + iNum);
          break;
      }
      return dTemp;
    }

    //sample usage
    var d = new Date();
    var d2 = d.add("d", 3); //+3days
    var d3 = d.add("h", -3); //-3hours
    var d4 = d.add("mo", 2); //+2 Months

McGarnagle · Answer 2 · 2012-06-29T07:02:53.790

0

Parse out the pieces and reconstruct:

function addMonths(d, offset)
{
    return new Date(d.getFullYear(), d.getMonth()+offset, d.getDate());
}

var d = new Date();
console.log(d.toDateString());
// Thu Jun 28 2012

var twoMonthsFromNow = addMonths(d, 2);
console.log(twoMonthsFromNow.toDateString());
// Sun Aug 28 112

edited Jun 29 '12 at 07:02

answered Jun 29 '12 at 06:55

McGarnagle

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panda-34 · Answer 3 · 2012-06-29T07:22:49.417

0

If you want to go into next month when days overflow, then

var d = new Date(2012, 6-1, 30);
d.setMonth(d.getMonth()+3);

if you want to stay within the new month,adjusting your date, then

var d = new Date(2012, 6-1, 30);
var add_months = 8
var d2 = new Date(Math.min(new Date(d.getYear(), d.getMonth()+add_months+1, 0),
              new Date(d.getYear(), d.getMonth()+add_months, d.getDate())))

edited Jun 29 '12 at 07:22

answered Jun 29 '12 at 06:59

panda-34

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JavaScript date calculation with months difference

3 Answers3