日积月累的js日期操作的方法，吐血奉献

 

<script language=Javascript>

String.prototype.Left = function(len){

        if(isNaN(len)||len==null){

                len = 0;

        } else {

         if(parseInt(len)<0||parseInt(len)>this.length) {

                        len = 0;

                }

        }

        return this.substr(0,this.length-len)+'**';

}

//日期自动补零程序

function appendZero(n)

{

        return(("00"+ n).substr(("00"+ n).length-2));

}

//获得当年当月最大天数

function GetMonthMaxDay(theYear,theMonth){  

  var theDays = new Array(31,28,31,30,31,30,31,31,30,31,30,31);

  var theMonthDay = 0, tmpYear = this.formatYear(theYear);

  theMonthDay = theDays[theMonth];

  if (theMonth == 1){ //theMonth is February

          if (((tmpYear % 4 == 0) && (tmpYear % 100 != 0)) || (tmpYear % 400 == 0)){

                  theMonthDay++;

          }

  }

  return(theMonthDay);

}

//把年份格式化成4位

function formatYear(theYear){  

  var tmpYear = parseInt(theYear,10);

  if (tmpYear < 100){

  tmpYear += 1900;

  if (tmpYear < 1940){

  tmpYear += 100;

  }

  }

  if (tmpYear < this.MinYear){

  tmpYear = this.MinYear;

  }

  if (tmpYear > this.MaxYear){

  tmpYear = this.MaxYear;

  }

  return(tmpYear);

}

//对javascript日期进行格式化

//formattype是返回的时间类型

//返回：返回时间串

function formatDate(day,formattype){

        var dateString = "";

        var thisyear = formatYear(day.getFullYear());

        var thismonth = appendZero(day.getMonth()+1);

        var thisday = appendZero(day.getDate());

        var thishour = appendZero(day.getHours());

        var thismin  = appendZero(day.getMinutes());

        var thissec  = appendZero(day.getSeconds());

        switch (formattype){

                case 0:

                        dateString = thisyear + "年" + thismonth + "月" + thisday + "日";

                        break;

                case 1:

                        dateString = thisyear + "-" + thismonth + "-" + thisday;

                        break;

                case 2:

                        dateString = thisyear + "-" + thismonth + "-" + thisday+ " " + appendZero(thishour) + ":" + appendZero(thismin) + ":" + appendZero(thissec);

                        break;

                default:

                        dateString = thisyear + "-" + thismonth + "-" + thisday;

        }

        return dateString;

}

//取得本周第一天

function getWeekFirstDay(formattype)

{

        var Nowdate=new Date();

        var WeekFirstDay=new Date(Nowdate-(Nowdate.getDay()-1)*86400000);

        return formatDate(WeekFirstDay,formattype);

}

//取得本周第七天

function getWeekLastDay(formattype)

{

        var Nowdate=new Date();

        var WeekFirstDay=new Date(Nowdate-(Nowdate.getDay()-1)*86400000);

        var WeekLastDay=new Date((WeekFirstDay/1000+6*86400)*1000);

        return formatDate(WeekLastDay,formattype);

}

function testDate() {

        var Nowdate=new Date();

        //本月

        var MonthFirstDay=new Date(Nowdate.getFullYear(),Nowdate.getMonth(),1);

        alert(MonthFirstDay.getFullYear())

        alert(appendZero(MonthFirstDay.getMonth()+1))

        //上月

        var lastMonth = new Date(Nowdate.getFullYear(),Nowdate.getMonth()-1,1);

        alert(lastMonth.getFullYear())

        alert(appendZero(lastMonth.getMonth()+1))

       

}

//取得本月第一天

function getMonthFirstDay(formattype)

{

        var Nowdate=new Date();

        var MonthFirstDay=new Date(Nowdate.getFullYear(),Nowdate.getMonth(),1);

        return formatDate(MonthFirstDay,formattype);

}

//取得本月最后一天

function getMonthLastDay(formattype)

{

        var Nowdate=new Date();

        var MonthNextFirstDay=new Date(Nowdate.getFullYear(),Nowdate.getMonth()+1,1);

        var MonthLastDay=new Date(MonthNextFirstDay-86400000);

        return formatDate(MonthLastDay,formattype);

}

function getDateFromString(strDate){

       

    var arrYmd = strDate.split("-");

    for(var i=0;i<arrYmd.length;i++){

            if(arrYmd[i].length>1 && arrYmd[i].indexOf("0")==0)

                    arrYmd[i]= arrYmd[i].substring(1);

    }

    var numYear = parseInt(arrYmd[0]);

    var numMonth = parseInt(arrYmd[1]) - 1;

    var numDay = parseInt(arrYmd[2]);

    return new Date(numYear, numMonth, numDay);

}

/*

下列函数返回需要的时间 偏移值不能大于30

参数：dadd是日偏移值，-表示向前推，+向后推

          formattype是返回的时间类型

返回：返回时间串

*/

function getDiffDate(dadd,formattype)

{

  //可以加上错误处理

        var a = new Date();

        a = a.valueOf();

        a = a + dadd * 24 * 60 * 60 * 1000;

        a = new Date(a);

        return formatDate(a,formattype);

}

//getDiffDate(+2,0)

//取得指定日期的年月日时分秒

//参数：dateValue 是格式形如：2007/04/05

function TimeCom(dateValue){

        var newCom = new Date(dateValue);

        this.year = newCom.getFullYear();

        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();

}

//取得两个日期之间的时间差

//参数：interval : y或year-表示取得相差的年份 n或month-表示相差的月份 d或day表示相差的天数 h或hour-表示相差的小时 m或minute-表示相差的分钟 s或second-表示相差的秒数 ms或msecond-表示相差的毫秒数 w或week-表示相差的周数

//      date1:起始日期

//      date2:结束日期

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);

}

/*

下列函数返回需要的时间 偏移值不能大于30

参数：interval : y或year-表示取得相差的年份 n或month-表示相差的月份 d或day表示相差的天数 h或hour-表示相差的小时 m或minute-表示相差的分钟 s或second-表示相差的秒数 ms或msecond-表示相差的毫秒数 w或week-表示相差的周数

      num是偏移值，-表示向前推，+向后推

          dateValue 指定的日期

          formattype是返回的时间类型

返回：返回时间串

*/

function DateAdd(interval,num,dateValue,formattype)

{

        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 formatDate(new Date(now),formattype);

}

//alert(DateAdd('d',-30,new Date(),0));

//取得当前日期

function getToDay(formattype){

        var Nowdate=new Date();

        M=Number(Nowdate.getMonth())+1;

        Nowdate = new Date(Nowdate.getFullYear()+"/"+M+"/"+Nowdate.getDate());

        return formatDate(Nowdate,formattype);

}

//上月第一天

function getPreviousFirstDay(formattype)

{

        var Nowdate=new Date();

        var MonthFirstDay=new Date(Nowdate.getFullYear(),Nowdate.getMonth()-1,1);

        return formatDate(MonthFirstDay,formattype);

}

//上月最后一天

function getPreviousLastDay(formattype)

{

        var Nowdate=new Date();

        var MonthFirstDay=new Date(Nowdate.getFullYear(),Nowdate.getMonth(),1);

        return formatDate(new Date(MonthFirstDay-86400000),formattype);

}

//上周第一天

function getPreviousFirstWeekDay(formattype)

{

        var Nowdate=new Date();

        var WeekFirstDay=new Date(Nowdate-(Nowdate.getDay()-1)*86400000);

        WeekFirstDay=new Date(WeekFirstDay-86400000*7);

        return formatDate(WeekFirstDay,formattype);

}

//上周最后一天

function showPreviousLastWeekDay(formattype)

{

        var Nowdate=new Date();

        var WeekFirstDay=new Date(Nowdate-(Nowdate.getDay()-1)*86400000);

        WeekFirstDay = new Date(WeekFirstDay-86400000);

        return formatDate(WeekFirstDay,formattype);

}

//上一天

function getPreviousDay(formattype)

{

        var MonthFirstDay=new Date();

        MonthFirstDay = new Date(MonthFirstDay-86400000);

        return formatDate(MonthFirstDay,formattype);

}

//下一天

function getNextDay(formattype)

{

        var MonthFirstDay=new Date();

        MonthFirstDay = new Date((MonthFirstDay/1000+86400)*1000);

        return formatDate(MonthFirstDay,formattype);

}

//下周第一天

function getNextFirstWeekDay(formattype)

{

        var Nowdate=new Date();

        var WeekFirstDay=new Date(Nowdate-(Nowdate.getDay()-1)*86400000);

        var MonthFirstDay=new Date((WeekFirstDay/1000+6*86400)*1000);

        MonthFirstDay=new Date((MonthFirstDay/1000+86400)*1000);

        return formatDate(MonthFirstDay,formattype);  

}

//下周最后一天

function getNextLastWeekDay(formattype)

{

        var Nowdate=new Date();

        var WeekFirstDay=new Date(Nowdate-(Nowdate.getDay()-1)*86400000);

        var WeekLastDay=new Date((WeekFirstDay/1000+6*86400)*1000);

        var MonthFirstDay=new Date((WeekLastDay/1000+7*86400)*1000);

        return formatDate(MonthFirstDay,formattype);  

}

//下月第一天

function getNextFirstDay(formattype)

{

        var Nowdate=new Date();

        var MonthFirstDay=new Date(Nowdate.getFullYear(),Nowdate.getMonth(),1);

        MonthFirstDay=new Date(MonthFirstDay.getYear(),MonthFirstDay.getMonth()+1,1);

        return formatDate(MonthFirstDay,formattype);

}

//下月最后一天

function getNextLastDay(formattype)

{

        var Nowdate=new Date();

        var MonthFirstDay=new Date(Nowdate.getFullYear(),Nowdate.getMonth(),1);

        MonthFirstDay=new Date(new Date(MonthFirstDay.getYear(),MonthFirstDay.getMonth()+2,1)-86400000);

        return formatDate(MonthFirstDay,formattype);

}

function getDateList(){

       

        var d = new Date('2007/07/07');

        alert(d.getMonth())

}

</script>

<input   name=haha   type=button   value="本周第一天"   onclick=alert(getWeekFirstDay(0))><br />   

<input   name=haha   type=button   value="本周第七天"   onclick=alert(getWeekLastDay(0))><br />   

<input   name=haha   type=button   value="本月第一天"   onclick=alert(getMonthFirstDay(0))><br />   

<input   name=haha   type=button   value="本月最后一天"   onclick=alert(getMonthLastDay(0))><br />

<input   name=haha   type=button   value="推前两天"   onclick=alert(getDiffDate(-2,0))><br />   

<input   name=haha   type=button   value="推后两天"   onclick=alert(getDiffDate(2,0))><br />

<input   name=haha   type=button   value="相差多个?"   onclick=alert(DateDiff('d','2007/04/05','2008/01/02'))><br />   

<input   name=haha   type=button   value="日期随意加减"   onclick=alert(DateAdd('d',2,'2007/04/05',0))><br />

<input   name=haha   type=button   value="取得当前日期"   onclick=alert(getToDay(0))><br />   

<input   name=haha   type=button   value="取得上月第一天"   onclick=alert(getPreviousFirstDay(0))><br />   

<input   name=haha   type=button   value="取得上月最后一天"   onclick=alert(getPreviousLastDay(0))><br />   

<input   name=haha   type=button   value="取得上周第一天"   onclick=alert(getPreviousFirstWeekDay(0))><br />   

<input   name=haha   type=button   value="取得上周最后一天"   onclick=alert(showPreviousLastWeekDay(0))><br />   

  

<input   name=haha   type=button   value="昨天"   onclick=alert(getPreviousDay(0))><br />   

<input   name=haha   type=button   value="今天"   onclick=alert(getToDay(0))><br />

<input   name=haha   type=button   value="明天"   onclick=alert(getNextDay(0))><br />   

<input   name=haha   type=button   value="下周第一天"   onclick=alert(getNextFirstWeekDay(0))><br />   

<input   name=haha   type=button   value="下周最后一天"   onclick=alert(getNextLastWeekDay(0))><br />   

<input   name=haha   type=button   value="下月第一天"   onclick=alert(getNextFirstDay(0))><br />   

<input   name=haha   type=button   value="下月最后一天"   onclick=alert(getDateFromString(2007-07-07))><br />

<input id=button type=button value="test"  onclick=alert('weixinjie'.Left(2))>

<input id=button type=button value="tt"  onclick=getDateList()>