var now = new Date();                    //当前日期  
	var nowDayOfWeek = now.getDay();         //今天本周的第几天
	if(nowDayOfWeek == 0){
	   nowDayOfWeek = 6;
	}else{
	   nowDayOfWeek = nowDayOfWeek - 1;
	}
	var nowDay = now.getDate();              //当前日  
	var nowMonth = now.getMonth();           //当前月  
	var nowYear = now.getYear();             //当前年  
	nowYear += (nowYear < 2000) ? 1900 : 0;  //  
	 
	//格式化日期：yyyy-MM-dd  
	function formatDate(date) {   
	    var myyear = date.getFullYear();  
	    var mymonth = date.getMonth()+1;  
	    var myweekday = date.getDate();   
	      
	    if(mymonth < 10){  
	        mymonth = "0" + mymonth;  
	    }   
	    if(myweekday < 10){  
	        myweekday = "0" + myweekday;  
	    }  
	    return (myyear+"-"+mymonth + "-" + myweekday);   
	}   
	 
	//获得某月的天数  
	function getMonthDays(myMonth){  
	    var monthStartDate = new Date(nowYear, myMonth, 1);   
	    var monthEndDate = new Date(nowYear, myMonth + 1, 1);   
	    var   days   =   (monthEndDate   -   monthStartDate)/(1000   *   60   *   60   *   24);   
	    return   days;   
	}  
	 
	//获得本季度的开始月份  
	function getQuarterStartMonth(){  
	    var quarterStartMonth = 0;  
	    if(nowMonth<3){  
	       quarterStartMonth = 0;  
	    }  
	    if(2<nowMonth && nowMonth<6){  
	       quarterStartMonth = 3;  
	    }  
	    if(5<nowMonth && nowMonth<9){  
	       quarterStartMonth = 6;  
	    }  
	    if(nowMonth>8){  
	       quarterStartMonth = 9;  
	    }  
	    return quarterStartMonth;  
	}  
	 
	//获得本周的开始日期  
	function getWeekStartDate() {
	    var weekStartDate = new Date(nowYear, nowMonth, nowDay - nowDayOfWeek);   
	    return formatDate(weekStartDate);  
	}   
	 
	//获得本周的结束日期  
	function getWeekEndDate() {   
	    var weekEndDate = new Date(nowYear, nowMonth, nowDay + (6 - nowDayOfWeek));   
	    return formatDate(weekEndDate);  
	}   
	 
	//获得本月的开始日期  
	function getMonthStartDate(){  
	    var monthStartDate = new Date(nowYear, nowMonth, 1);   
	    return formatDate(monthStartDate);  
	}  
	 
	//获得本月的结束日期  
	function getMonthEndDate(){  
	    var monthEndDate = new Date(nowYear, nowMonth, getMonthDays(nowMonth));   
	    return formatDate(monthEndDate);  
	}  
	 
	//获得本季度的开始日期  
	function getQuarterStartDate(){        
	    var quarterStartDate = new Date(nowYear, getQuarterStartMonth(), 1);   
	    return formatDate(quarterStartDate);  
	}  
	 
	//或的本季度的结束日期  
	function getQuarterEndDate(){  
	    var quarterEndMonth = getQuarterStartMonth() + 2;  
	    var quarterStartDate = new Date(nowYear, quarterEndMonth, getMonthDays(quarterEndMonth));   
	    return formatDate(quarterStartDate);  
	}
	//获得本年的开始日期  
	function getYearStartDate(){
	    var yearStartDate = new Date(nowYear, 0, 1);   
	    return formatDate(yearStartDate);
	}
	//获得本年的结束日期
	function getYearEndDate(){
	var yearEndDate = new Date(nowYear, 11, 31);   
	    return formatDate(yearEndDate);
	}
	//获得当前日期
	function getNowDate(){
	    return formatDate(new Date());
	}

?

var?nowDayOfWeek?=?now.getDay();?????????//今天本周的第几天???

国外是以“周日” 为一周的开始 从0开始

周日 周一 周二 周三 周四 周五 周六

0??????? 1????? 2???? 3???? 4???? 5????? 6

按照国内从“周一”开始需要进行判断

?

周一 周二 周三 周四 周五 周六 周日

?0??????1?????2?????3?????4??????5????? 6

?

代码如下：

if(nowDayOfWeek == 0){
	   nowDayOfWeek = 6;
	}else{
	   nowDayOfWeek = nowDayOfWeek - 1;
	}

?

?

?