JavaScript中可以使用Date对象中的方法来获取当前日期。使用var myDate=new Date()创建date对象，然后使用toLocaleDateString()方法获取当前日期。

Date对象用于处理日期和时间。

创建Date对象的语法：

var myDate=new Date()

注释：Date 对象会自动把当前日期和时间保存为其初始值。

date对象获取时间日期的方法如下：

myDate.getYear(); //获取当前年份(2位)
myDate.getFullYear(); //获取完整的年份(4位,1970-"htmlcode">

//--------------------------------------------------- 
// 判断闰年 
//--------------------------------------------------- 
Date.prototype.isLeapYear = function() 
{ 
return (0==this.getYear()%4&&((this.getYear()%100!=0)||(this.getYear()%400==0))); 
} 
//--------------------------------------------------- 
// 日期格式化 
// 格式 YYYY/yyyy/YY/yy 表示年份 
// MM/M 月份 
// W/w 星期 
// dd/DD/d/D 日期 
// hh/HH/h/H 时间 
// mm/m 分钟 
// ss/SS/s/S 秒 
//--------------------------------------------------- 
Date.prototype.Format = function(formatStr) 
{ 
var str = formatStr; 
var Week = ['日','一','二','三','四','五','六']; 
str=str.replace(/yyyy|YYYY/,this.getFullYear()); 
str=str.replace(/yy|YY/,(this.getYear() % 100)>9?(this.getYear() % 100).toString():'0' + (this.getYear() % 100)); 
str=str.replace(/MM/,this.getMonth()>9?this.getMonth().toString():'0' + this.getMonth()); 
str=str.replace(/M/g,this.getMonth()); 
str=str.replace(/w|W/g,Week[this.getDay()]); 
str=str.replace(/dd|DD/,this.getDate()>9?this.getDate().toString():'0' + this.getDate()); 
str=str.replace(/d|D/g,this.getDate()); 
str=str.replace(/hh|HH/,this.getHours()>9?this.getHours().toString():'0' + this.getHours()); 
str=str.replace(/h|H/g,this.getHours()); 
str=str.replace(/mm/,this.getMinutes()>9?this.getMinutes().toString():'0' + this.getMinutes()); 
str=str.replace(/m/g,this.getMinutes()); 
str=str.replace(/ss|SS/,this.getSeconds()>9?this.getSeconds().toString():'0' + this.getSeconds()); 
str=str.replace(/s|S/g,this.getSeconds()); 
return str; 
} 
//+--------------------------------------------------- 
//| 求两个时间的天数差 日期格式为 YYYY-MM-dd 
//+--------------------------------------------------- 
function daysBetween(DateOne,DateTwo) 
{ 
var OneMonth = DateOne.substring(5,DateOne.lastIndexOf ('-')); 
var OneDay = DateOne.substring(DateOne.length,DateOne.lastIndexOf ('-')+1); 
var OneYear = DateOne.substring(0,DateOne.indexOf ('-')); 
var TwoMonth = DateTwo.substring(5,DateTwo.lastIndexOf ('-')); 
var TwoDay = DateTwo.substring(DateTwo.length,DateTwo.lastIndexOf ('-')+1); 
var TwoYear = DateTwo.substring(0,DateTwo.indexOf ('-')); 
var cha=((Date.parse(OneMonth+'/'+OneDay+'/'+OneYear)- Date.parse(TwoMonth+'/'+TwoDay+'/'+TwoYear))/86400000); 
return Math.abs(cha); 
} 
//+--------------------------------------------------- 
//| 日期计算 
//+--------------------------------------------------- 
Date.prototype.DateAdd = function(strInterval, Number) { 
var dtTmp = this; 
switch (strInterval) { 
case 's' :return new Date(Date.parse(dtTmp) + (1000 * Number)); 
case 'n' :return new Date(Date.parse(dtTmp) + (60000 * Number)); 
case 'h' :return new Date(Date.parse(dtTmp) + (3600000 * Number)); 
case 'd' :return new Date(Date.parse(dtTmp) + (86400000 * Number)); 
case 'w' :return new Date(Date.parse(dtTmp) + ((86400000 * 7) * Number)); 
case 'q' :return new Date(dtTmp.getFullYear(), (dtTmp.getMonth()) + Number*3, dtTmp.getDate(), dtTmp.getHours(), dtTmp.getMinutes(), dtTmp.getSeconds()); 
case 'm' :return new Date(dtTmp.getFullYear(), (dtTmp.getMonth()) + Number, dtTmp.getDate(), dtTmp.getHours(), dtTmp.getMinutes(), dtTmp.getSeconds()); 
case 'y' :return new Date((dtTmp.getFullYear() + Number), dtTmp.getMonth(), dtTmp.getDate(), dtTmp.getHours(), dtTmp.getMinutes(), dtTmp.getSeconds()); 
} 
} 
//+--------------------------------------------------- 
//| 比较日期差 dtEnd 格式为日期型或者 有效日期格式字符串 
//+--------------------------------------------------- 
Date.prototype.DateDiff = function(strInterval, dtEnd) { 
var dtStart = this; 
if (typeof dtEnd == 'string' )//如果是字符串转换为日期型 
{ 
dtEnd = StringToDate(dtEnd); 
} 
switch (strInterval) { 
case 's' :return parseInt((dtEnd - dtStart) / 1000); 
case 'n' :return parseInt((dtEnd - dtStart) / 60000); 
case 'h' :return parseInt((dtEnd - dtStart) / 3600000); 
case 'd' :return parseInt((dtEnd - dtStart) / 86400000); 
case 'w' :return parseInt((dtEnd - dtStart) / (86400000 * 7)); 
case 'm' :return (dtEnd.getMonth()+1)+((dtEnd.getFullYear()-dtStart.getFullYear())*12) - (dtStart.getMonth()+1); 
case 'y' :return dtEnd.getFullYear() - dtStart.getFullYear(); 
} 
} 
//+--------------------------------------------------- 
//| 日期输出字符串，重载了系统的toString方法 
//+--------------------------------------------------- 
Date.prototype.toString = function(showWeek) 
{ 
var myDate= this; 
var str = myDate.toLocaleDateString(); 
if (showWeek) 
{ 
var Week = ['日','一','二','三','四','五','六']; 
str += ' 星期' + Week[myDate.getDay()]; 
} 
return str; 
} 
//+--------------------------------------------------- 
//| 日期合法性验证 
//| 格式为：YYYY-MM-DD或YYYY/MM/DD 
//+--------------------------------------------------- 
function IsValidDate(DateStr) 
{ 
var sDate=DateStr.replace(/(^\s+|\s+$)/g,''); //去两边空格; 
if(sDate=='') return true; 
//如果格式满足YYYY-(/)MM-(/)DD或YYYY-(/)M-(/)DD或YYYY-(/)M-(/)D或YYYY-(/)MM-(/)D就替换为'' 
//数据库中，合法日期可以是:YYYY-MM/DD(2003-3/21),数据库会自动转换为YYYY-MM-DD格式 
var s = sDate.replace(/[\d]{ 4,4 }[\-/]{ 1 }[\d]{ 1,2 }[\-/]{ 1 }[\d]{ 1,2 }/g,''); 
if (s=='') //说明格式满足YYYY-MM-DD或YYYY-M-DD或YYYY-M-D或YYYY-MM-D 
{ 
var t=new Date(sDate.replace(/\-/g,'/')); 
var ar = sDate.split(/[-/:]/); 
if(ar[0] != t.getYear() || ar[1] != t.getMonth()+1 || ar[2] != t.getDate()) 
{ 
//alert('错误的日期格式！格式为：YYYY-MM-DD或YYYY/MM/DD。注意闰年。'); 
return false; 
} 
} 
else 
{ 
//alert('错误的日期格式！格式为：YYYY-MM-DD或YYYY/MM/DD。注意闰年。'); 
return false; 
} 
return true; 
} 
//+--------------------------------------------------- 
//| 日期时间检查 
//| 格式为：YYYY-MM-DD HH:MM:SS 
//+--------------------------------------------------- 
function CheckDateTime(str) 
{ 
var reg = /^(\d+)-(\d{ 1,2 })-(\d{ 1,2 }) (\d{ 1,2 }):(\d{ 1,2 }):(\d{ 1,2 })$/; 
var r = str.match(reg); 
if(r==null)return false; 
r[2]=r[2]-1; 
var d= new Date(r[1],r[2],r[3],r[4],r[5],r[6]); 
if(d.getFullYear()!=r[1])return false; 
if(d.getMonth()!=r[2])return false; 
if(d.getDate()!=r[3])return false; 
if(d.getHours()!=r[4])return false; 
if(d.getMinutes()!=r[5])return false; 
if(d.getSeconds()!=r[6])return false; 
return true; 
} 
//+--------------------------------------------------- 
//| 把日期分割成数组 
//+--------------------------------------------------- 
Date.prototype.toArray = function() 
{ 
var myDate = this; 
var myArray = Array(); 
myArray[0] = myDate.getFullYear(); 
myArray[1] = myDate.getMonth(); 
myArray[2] = myDate.getDate(); 
myArray[3] = myDate.getHours(); 
myArray[4] = myDate.getMinutes(); 
myArray[5] = myDate.getSeconds(); 
return myArray; 
} 
//+--------------------------------------------------- 
//| 取得日期数据信息 
//| 参数 interval 表示数据类型 
//| y 年 m月 d日 w星期 ww周 h时 n分 s秒 
//+--------------------------------------------------- 
Date.prototype.DatePart = function(interval) 
{ 
var myDate = this; 
var partStr=''; 
var Week = ['日','一','二','三','四','五','六']; 
switch (interval) 
{ 
case 'y' :partStr = myDate.getFullYear();break; 
case 'm' :partStr = myDate.getMonth()+1;break; 
case 'd' :partStr = myDate.getDate();break; 
case 'w' :partStr = Week[myDate.getDay()];break; 
case 'ww' :partStr = myDate.WeekNumOfYear();break; 
case 'h' :partStr = myDate.getHours();break; 
case 'n' :partStr = myDate.getMinutes();break; 
case 's' :partStr = myDate.getSeconds();break; 
} 
return partStr; 
} 
//+--------------------------------------------------- 
//| 取得当前日期所在月的最大天数 
//+--------------------------------------------------- 
Date.prototype.MaxDayOfDate = function() 
{ 
var myDate = this; 
var ary = myDate.toArray(); 
var date1 = (new Date(ary[0],ary[1]+1,1)); 
var date2 = date1.dateAdd(1,'m',1); 
var result = dateDiff(date1.Format('yyyy-MM-dd'),date2.Format('yyyy-MM-dd')); 
return result; 
} 
//+--------------------------------------------------- 
//| 取得当前日期所在周是一年中的第几周 
//+--------------------------------------------------- 
Date.prototype.WeekNumOfYear = function() 
{ 
var myDate = this; 
var ary = myDate.toArray(); 
var year = ary[0]; 
var month = ary[1]+1; 
var day = ary[2]; 
document.write('< script language=VBScript\> \n'); 
document.write('myDate = DateValue(''+month+'-'+day+'-'+year+'') \n'); 
document.write('result = DatePart('ww', myDate) \n'); 
document.write(' \n'); 
return result; 
} 
//+--------------------------------------------------- 
//| 字符串转成日期类型 
//| 格式 MM/dd/YYYY MM-dd-YYYY YYYY/MM/dd YYYY-MM-dd 
//+--------------------------------------------------- 
function StringToDate(DateStr) 
{ 
var converted = Date.parse(DateStr); 
var myDate = new Date(converted); 
if (isNaN(myDate)) 
{ 
//var delimCahar = DateStr.indexOf('/')!=-1?'/':'-'; 
var arys= DateStr.split('-'); 
myDate = new Date(arys[0],--arys[1],arys[2]); 
} 
return myDate; 
}