JavaScript日期操作（周，月，季度，年）

<mce:script type="text/javascript"> 

<!-- 

    //当天 

     function showToDay() 

    { 

        var Nowdate=new Date(); 

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

        return Nowdate.getYear()+"-"+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.getYear(),Nowdate.getMonth(),1); 

        return MonthFirstDay; 

    } 

  

    //本月最后一天  

 

     function showMonthLastDay() 

    { 

        var Nowdate=new Date(); 

        var tmpDate=new Date(Nowdate.getYear(),Nowdate.getMonth()+1,1); 

        //tmpDate.setDate(tmpDate.getDate() -1); 

        //return new Date(Nowdate.getYear(),Nowdate.getMonth(),tmpDate.getDate());  

        var MonthLastDay=new Date(tmpDate-86400000); 

        return MonthLastDay;  

 

    } 

 

     

    //本季第一天 

     function showquarterFirstDay() 

    { 

        var Nowdate=new Date(); 

        if(Nowdate.getMonth()<3)  

           return new Date(Nowdate.getYear(),0,1); 

        else if(Nowdate.getMonth()>2 && Nowdate.getMonth()<6)  

           return new Date(Nowdate.getYear(),3,1);  

        else if(Nowdate.getMonth()>5 && Nowdate.getMonth()<9)  

           return new Date(Nowdate.getYear(),6,1); 

        else if(Nowdate.getMonth()>8)  

           return new Date(Nowdate.getYear(),9,1); 

    } 

  

    //本季最后一天 

     function showquarterLastDay() 

    { 

        var Nowdate=new Date();  

 

        if(Nowdate.getMonth()<3)  

           return new Date(Nowdate.getYear(),2,31); 

        else if(Nowdate.getMonth()>2 && Nowdate.getMonth()<6)  

           return new Date(Nowdate.getYear(),5,30); 

        else if(Nowdate.getMonth()>5 && Nowdate.getMonth()<9)  

           return new Date(Nowdate.getYear(),8,30); 

        else if(Nowdate.getMonth()>8)  

           return new Date(Nowdate.getYear(),11,31); 

    } 

  

     

    //本年第一天 

     function showyearFirstDay() 

    { 

        var Nowdate=new Date(); 

        var yearFirstDay=new Date(Nowdate.getYear(),0,1); 

        return yearFirstDay; 

    } 

  

    //本年最后一天 

     function showyearLastDay() 

    { 

        var Nowdate=new Date(); 

        var yearLastDay=new Date(Nowdate.getYear(),11,31); 

        return yearLastDay; 

    } 

  

     

    //当前月 

     function showmonthCurrent() 

    { 

        var Nowdate=new Date(); 

        var Month=Nowdate.getMonth()+1; 

        Month=(Month<10)?'-0'+Month:'-'+Month; 

        return Nowdate.getYear()+Month; 

    }  

     

    //本季开始年月 

     function showquarterFirstMonth() 

    { 

        var Nowdate=new Date(); 

        if(Nowdate.getMonth()<3) 

            return Nowdate.getYear()+'-01'; 

        else if(Nowdate.getMonth()>2 && Nowdate.getMonth()<6) 

            return Nowdate.getYear()+'-04';  

        else if(Nowdate.getMonth()>5 && Nowdate.getMonth()<9) 

            return Nowdate.getYear()+'-07'; 

        else if(Nowdate.getMonth()>8) 

            return Nowdate.getYear()+'-10'; 

    } 

  

    //本季最后年月 

     function showquarterLastMonth() 

    { 

        var Nowdate=new Date();  

        if(Nowdate.getMonth()<3) 

            return Nowdate.getYear()+'-03'; 

        else if(Nowdate.getMonth()>2 && Nowdate.getMonth()<6) 

            return Nowdate.getYear()+'-06'; 

        else if(Nowdate.getMonth()>5 && Nowdate.getMonth()<9) 

            return Nowdate.getYear()+'-09'; 

        else if(Nowdate.getMonth()>8) 

            return Nowdate.getYear()+'-12'; 

    } 

  

     

    //本年开始年月 

     function showyearFirstMonth()  

    { 

        var Nowdate=new Date(); 

        return Nowdate.getYear()+'-01'; 

    } 

  

    //本年最后年月 

     function showyearLastMonth() 

    { 

        var Nowdate=new Date(); 

        return Nowdate.getYear()+'-12'; 

    } 

    //格式化日期格式 

     function Date.prototype.toString(){ 

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

    }  

// --> 

</mce:script>