日期计算

var flag = Array();
for(var i=0; i<flag.length; i++){
  document.write(flag[i]+"\n\r");
}
//设置周期内的日期数组
function SetFlag(start,end){
var cdate = Array();
cdate = start.split("-");
var cd = cdate[1]+"/"+cdate[2]+"/"+cdate[0]; 
var dayNum = DateDiff(end,start);
return dayNum;
/*for(var i=0; i<=dayNum; i++){
flag.push(AddDays(cd,i));
}*/
}
//日期加上天数后的新日期
function AddDays(date,days){
var nd = new Date(date);
nd = nd.valueOf();
nd = nd + days * 24 * 60 * 60 * 1000;
nd = new Date(nd);
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;
}
//两个日期的差值(d2 - d1)
function DateDiff(d1,d2){
var day = 24 * 60 * 60 *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 = parseInt((checkTime2 - checkTime)/day); 
  return cha;
}catch(e){
return false;
}
}