获取本周、本季度、本月、上月的开始日期、结束日期

https://www.cnblogs.com/liyixiang/p/6038122.html

/**

* 获取本周、本季度、本月、上月的开始日期、结束日期

*/

var now = new Date(); //当前日期

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

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; //

var lastMonthDate = new Date(); //上月日期

lastMonthDate.setDate(1);

lastMonthDate.setMonth(lastMonthDate.getMonth()-1);

var lastYear = lastMonthDate.getYear();

var lastMonth = lastMonthDate.getMonth();

//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