JS date plus minus, date operation code _ time Date

One, date minus days equals second date

function cc (DD,DADD) {
//can be added error handling
var a = new Date (dd)
a = a.valueof ()
a = a-dadd * * * * * 1000
   a = new Date (a)
alert (a.getfullyear () + "year" + (A.getmonth () + 1) + "month" + a.getdate () + "Day")
}
cc ("12/23/200 2 ", 2)

Here we have to add, waste a lot of time to learn:
Javascript's code for TIME
0-11 number Expression January-December: Var a= new Date (2006,5,6) turns out to be 2006-6-6
0-6 means week
1-31 means date
0-23 hours
0-59 minutes, seconds.

Two. Two-date difference (D1-D2).

function DateDiff (D1,D2) {var day = * * *
  *1000;
try{  
    var Datearr = d1.split ("-");
  var checkdate = new Date ();
    Checkdate.setfullyear (Datearr[0], datearr[1]-1, datearr[2]);
  var checktime = Checkdate.gettime ();
 
  var dateArr2 = D2.split ("-");
  var checkDate2 = new Date ();
    Checkdate2.setfullyear (Datearr2[0], datearr2[1]-1, datearr2[2]);
  var checkTime2 = Checkdate2.gettime ();
  
  var cha = (checktime-checktime2)/day; 
    return cha;
  catch (e) {return
  false;
}
} End Fun

Third, the application:

<script language= "javascript" type= "Text/javascript" > var flag = Array ();//global variable var start = "2009-01-01";
var end = "2009-02-24"; 

Setflag (Start,end);

for (var i=0; i<flag.length; i++) {document.write (flag[i]+ "\n\r");} Set Date (array) function Setflag (start,end) {var cdate = array (); CDate = Start.split ("-"); var cd = cdate[1]+ "/" +cdate[2]+ 
"/" +cdate[0];
var daynum = DateDiff (End,start); for (var i=0; i<=daynum; i++) {Flag.push (AddDays (Cd,i));}
End fun//date plus days after the new date.
  function AddDays (date,days) {var nd = new Date (date);
  nd = nd.valueof ();
  nd = nd + days * 24 * 60 * 60 * 1000;
  nd = new Date (ND);
Alert (nd.getfullyear () + "year" + (Nd.getmonth () + 1) + "month" + nd.getdate () + "Day");
var y = nd.getfullyear ();
var m = nd.getmonth () +1;
var d = nd.getdate ();
if (M <= 9) m = "0" +M; 
if (d <= 9) d = "0" +D;
var cdate = y+ "-" +m+ "-" +D;
return cdate;
}//Two-date difference (D1-D2).
 function DateDiff (D1,D2) {var day = *1000 try{var Datearr = d1.split ("-"); var checkdate = new Date ();
  Checkdate.setfullyear (Datearr[0], datearr[1]-1, datearr[2]);
 
  var checktime = Checkdate.gettime ();
  var dateArr2 = D2.split ("-");
    var checkDate2 = new Date ();
  Checkdate2.setfullyear (Datearr2[0], datearr2[1]-1, datearr2[2]);
  
  var checkTime2 = Checkdate2.gettime (); 
    var cha = (checktime-checktime2)/day;
  return cha; }catch (e) {return false;}} End Fun </script>