JS日期加减,日期运算代码

一、日期减去天数等于第二个日期

function cc(dd,dadd){
//可以加上错误处理
var a = new date(dd)
a = a.valueof()
a = a - dadd * 24 * 60 * 60 * 1000
a = new date(a)
alert(a.getfullyear() + "年" + (a.getmonth() + 1) + "月" + a.getdate() + "日")
}
cc("12/23/2002",2)

这里不得不做补充,浪费好多时间得出教训:
javascript 对时间的代号
0-11数字表示1-12月: var a= new date(2006,5,6) 结果是2006-6-6
0-6表示星期
1-31表示日期
0-23小时
0-59分钟,秒

二。//两个日期的差值(d1 - d2).

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 = (checktime - checktime2)/day; 
    return cha;
  }catch(e){
  return false;
}
}//end fun

三、应用：

<script language="javascript" type="text/javascript">
var flag = array();//全局变量

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");
}

//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);
for(var i=0; i<=daynum; i++){
  flag.push(adddays(cd,i));
}
}//end fun
//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);
  //alert(nd.getfullyear() + "年" + (nd.getmonth() + 1) + "月" + nd.getdate() + "日");
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(d1 - d2).
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 = (checktime - checktime2)/day; 
    return cha;
  }catch(e){
  return false;
}
}//end fun
</script>