my regex isnt working

[solarisuser]

I'm trying to add 180 days to an existing date, and then make sure if the month is a single digit, I want to add a 0 before it.

For some reason its just not working, I am hoping someone can point out my error... thanks!

 

	var dateStr = "08/22/2001";
	var millis = Date.parse(dateStr);
	var newDate = new Date();
	newDate.setTime(millis  + 180 *24*60*60*1000);
	var newDateStr = "" + (newDate.getMonth()+1) + "/" + newDate.getDate() + "/" + newDate.getFullYear();
	myarray = newDateStr.split(/\//);
	if( myarray[0] <= 9 && myarray[0] >= 0)
	{ 
		var save = "/" + myarray[0] + "/";
		alert(myarray[0]);
		newmonth = "0"+myarray[0]+"/";
		alert(newmonth );
		myregexp = save+"/";
		alert(myregexp);
		newDateStr2 = newDateStr.replace(myregexp, newmonth );
		alert(newDateStr2);

	}

[jacksonmj]

I'm still not quite sure what's wrong with your original code, but it would be much simpler (and easier) to use something like the following (note this also makes sure that the day is two digits):

 

var dateStr = "08/22/2001";
var millis = Date.parse(dateStr);
var newDate = new Date();
newDate.setTime(millis  + 180*24*60*60*1000);
var newDateStr = "";
if (newDate.getMonth() < 9)
newDateStr += "0";
newDateStr += (newDate.getMonth()+1)+"\/";
if (newDate.getDate() < 10)
newDateStr += "0";
newDateStr += newDate.getDate()+"\/"+newDate.getFullYear();
alert(newDateStr);

 

[Psycho]

I could probably do this in several fewer lines using a one line regular expression, but my brain can't process regEx this late at night. I think this is a little more elegant.

 

MORE IMPORTANTLY: The code in the previous two posts will not calculate correctly for abourt 1/2 the dates (8/22/2001 being one of them due to daylight savings going back for the fall equinox). because the date you used to create the original timestamp has no time it is assumed to be midnight. With 8/22/2001 if you add 24 hours x 180 days it will only take you to 10PM on the 179th day. I added four hours as a buffer to account for that.

 

  var dateStr = "08/22/2001";
  var millis = Date.parse(dateStr);
  var newDate = new Date();
  //Create new date object +180 days &
  // +4 hours so daylight savings won't mess it up
  newDate.setTime(millis+(180*24*60*60*1000)+(4*60*60*1000));

  //Create string objects of month & day with 0 appended
  //Then take jsut the last two characters
  var month = String('0'+(newDate.getMonth()+1));
      month = month.substr((month.length-2), 2);
  var day   = String('0'+newDate.getDate());
      day   = day.substr((day.length-2), 2);
  var year  = String(newDate.getFullYear());

  //Create new date string
  var newDateStr = month+'/'+day+'/'+year;

  alert(newDateStr);