javascript的日期加减

javascript的日期加减

function TimeCom( dateValue )
{
var newCom = new Date( dateValue );
this.year = newCom.getYear();
this.month = newCom.getMonth()+1;
this.day = newCom.getDate();
this.hour = newCom.getHours();
this.minute = newCom.getMinutes();
this.second = newCom.getSeconds();
this.msecond = newCom.getMilliseconds();
this.week = newCom.getDay();
}

function DateDiff(interval,date1,date2)
{
var TimeCom1 = new TimeCom(date1);
var TimeCom2 = new TimeCom(date2);
var result;
switch(String(interval).toLowerCase())
{
case "y":
case "year":
result = TimeCom1.year-TimeCom2.year;
break;
case "n":
case "month":
result = (TimeCom1.year-TimeCom2.year)*12+(TimeCom1.month-TimeCom2.month);
break;
case "d":
case "day":
result = Math.round((Date.UTC(TimeCom1.year,TimeCom1.month-1,TimeCom1.day)-Date.UTC(TimeCom2.year,TimeCom2.month-1,TimeCom2.day))/(1000*60*60*24));
break;
case "h":
case "hour":
result = Math.round((Date.UTC(TimeCom1.year,TimeCom1.month-1,TimeCom1.day,TimeCom1.hour)-Date.UTC(TimeCom2.year,TimeCom2.month-1,TimeCom2.day,TimeCom2.hour))/(1000*60*60));
break;
case "m":
case "minute":
result = Math.round((Date.UTC(TimeCom1.year,TimeCom1.month-1,TimeCom1.day,TimeCom1.hour,TimeCom1.minute)-Date.UTC(TimeCom2.year,TimeCom2.month-1,TimeCom2.day,TimeCom2.hour,TimeCom2.minute))/(1000*60));
break;
case "s":
case "second":
result = Math.round((Date.UTC(TimeCom1.year,TimeCom1.month-1,TimeCom1.day,TimeCom1.hour,TimeCom1.minute,TimeCom1.second)-Date.UTC(TimeCom2.year,TimeCom2.month-1,TimeCom2.day,TimeCom2.hour,TimeCom2.minute,TimeCom2.second))/1000);
break;
case "ms":
case "msecond":
result = Date.UTC(TimeCom1.year,TimeCom1.month-1,TimeCom1.day,TimeCom1.hour,TimeCom1.minute,TimeCom1.second,TimeCom1.msecond)-Date.UTC(TimeCom2.year,TimeCom2.month-1,TimeCom2.day,TimeCom2.hour,TimeCom2.minute,TimeCom2.second,TimeCom1.msecond);
break;
case "w":
case "week":
result = Math.round((Date.UTC(TimeCom1.year,TimeCom1.month-1,TimeCom1.day)-Date.UTC(TimeCom2.year,TimeCom2.month-1,TimeCom2.day))/(1000*60*60*24)) % 7;
break;
default:
result = "invalid";
}
return(result);
}

function DateAdd(interval, num, dateValue)
{
var newCom = new TimeCom(dateValue);
switch(String(interval).toLowerCase())
{
case "y": case "year": newCom.year += num; break;
case "n": case "month": newCom.month += num; break;
case "d": case "day": newCom.day += num; break;
case "h": case "hour": newCom.hour += num; break;
case "m": case "minute": newCom.minute += num; break;
case "s": case "second": newCom.second += num; break;
case "ms": case "msecond": newCom.msecond += num; break;
case "w": case "week": newCom.day += num*7; break;
default: return("invalid");
}
var now = newCom.year+"/"+newCom.month+"/"+newCom.day+" "+newCom.hour+":"+newCom.minute+":"+newCom.second;
return(new Date(now));
}

2.另一个简单例子
日期减去天数等于第二个日期
<script language=Javascript>
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)
</script>
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

原文地址:http://www.cnblogs.com/linbaba/archive/2006/12/05/583173.html