JavaScript的取日期的問題

PS:getYear()有Y2K問題所以建議全部轉用getFullYear();

PS:DATE對象GETYEAR(）方法和GETFULLYEAR()方法區別

getYear()

使用getYear()函數的本意是獲取年份，以2010年為例，如：

Js代碼

var nowd = new Date();

var yf = nowd.getYear();

在IE中是可以正確獲取年份：2010，但是在FF等瀏覽器下則為：110。

原因則是在FF等瀏覽器內getYear 返回的是"當前年份-1900" 的值（即年份基數是1900）

而IE則是當today的年份大於等於2000的時，直接將1900加上了，返回的2010。

getFullYear()

使用getFullYear()在IE和FF中都可以正確獲取年份：2010

注意

使用js來獲取年份都使用：getFullYear()

//算出今天和上一個月

function LastMonth(){

var nowdate = new Date();

var lastdate = new Date();

nowdate.setMonth(nowdate.getMonth()+1);//算當月要加1

lastdate.setMonth(nowdate.getMonth()-1);

nowdate = nowdate.getFullYear()+"-"+nowdate.getMonth()+"-"+nowdate.getDate();

lastdate = lastdate.getFullYear()+"-"+lastdate.getMonth()+"-"+lastdate.getDate();

date_html = lastdate + ' ~ ' + nowdate ;

}

//----------------以下方式為舊的方式參考就好---------------------------------------------

//今天

function showToDay()

{

var Nowdate=new Date();

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

return Nowdate.getFullYear()+"-"+M+"-"+Nowdate.getDate();

}

//本周第一天

function showWeekFirstDay()

{

var Nowdate=new Date();

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

return WeekFirstDay;

}

//本周最后一天

function showWeekLastDay()

{

var Nowdate=new Date();

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

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

return WeekLastDay;

}

//本月第一天

function showMonthFirstDay()

{

var Nowdate=new Date();

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

return MonthFirstDay;

}

//本月最後一天

function showMonthLastDay()

{

var Nowdate=new Date();

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

var MonthLastDay=new Date(MonthNextFirstDay-86400000);

return MonthLastDay;

}

//上月第一天

function showPreviousFirstDay()

{

var MonthFirstDay=showMonthFirstDay()

return new Date(MonthFirstDay.getFullYear(),MonthFirstDay.getMonth()-1,1)

}

//上月最後一天

function showPreviousLastDay()

{

var MonthFirstDay=showMonthFirstDay();

return new Date(MonthFirstDay-86400000);

}

//上周第一天

function showPreviousFirstWeekDay()

{

var WeekFirstDay=showWeekFirstDay()

return new Date(WeekFirstDay-86400000*7)

}

//上周最後一天

function showPreviousLastWeekDay()

{

var WeekFirstDay=showWeekFirstDay()

return new Date(WeekFirstDay-86400000)

}

//上一天

function showPreviousDay()

{

var MonthFirstDay=new Date();

return new Date(MonthFirstDay-86400000);

}

//下一天

function showNextDay()

{

var MonthFirstDay=new Date();

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

}

//下周第一天

function showNextFirstWeekDay()

{

var MonthFirstDay=showWeekLastDay()

return new Date((MonthFirstDay/1000+86400)*1000)

}

//下周最後一天

function showNextLastWeekDay()

{

var MonthFirstDay=showWeekLastDay()

return new Date((MonthFirstDay/1000+7*86400)*1000)

}

//下月第一天

function showNextFirstDay()

{

var MonthFirstDay=showMonthFirstDay()

return new Date(MonthFirstDay.getFullYear(),MonthFirstDay.getMonth()+1,1)

}

//下月最後一天

function showNextLastDay()

{

var MonthFirstDay=showMonthFirstDay()

return new Date(new Date(MonthFirstDay.getFullYear(),MonthFirstDay.getMonth()+2,1)-86400000)

}

function Date.prototype.toString(){

return this.getFullYear()+"-"+(this.getMonth()+1)+"-"+this.getDate();

}

function setDate(num){

if(num==1){

document.all.dateDate.value=showMonthFirstDay();

document.all.dateDate2.value=showMonthLastDay();

}

if(num==2){

document.all.dateDate.value=showWeekFirstDay();

document.all.dateDate2.value=showWeekLastDay();

}

if(num==3){

document.all.dateDate.value=showToDay();

document.all.dateDate2.value=showToDay();

}

if(num==4){

document.all.dateDate.value=showPreviousFirstDay();

document.all.dateDate2.value=showPreviousLastDay();

}

if(num==5){

document.all.dateDate.value=showNextFirstDay();

document.all.dateDate2.value=showNextLastDay();

}

if(num==6){

document.all.dateDate.value=showPreviousFirstWeekDay();

document.all.dateDate2.value=showPreviousLastWeekDay();

}

if(num==7){

document.all.dateDate.value=showNextFirstWeekDay();

document.all.dateDate2.value=showNextLastWeekDay();

}

if(num==8){

document.all.dateDate.value=showPreviousDay();

document.all.dateDate2.value=showPreviousDay();

}

if(num==9){

document.all.dateDate.value=showNextDay();

document.all.dateDate2.value=showNextDay();

}

</script>