以周，月，季度 为单位作为开始，结束的时间查询

网传下面那段代码无BUG, 我可是程序安东尼，Bug万花筒，打法像极了皮尔斯

• 获取上周、本周、上月、本月、上季度、本季度的开始日期、结束日期
• 获取上月开始结束日期考虑了年份的变化
• “亲测无bug”

var now = new Date(); //当前日期 
var nowDayOfWeek = now.getDay()-1; //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 < 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); 
} 

//获得上周的开始日期 
function getLastWeekStartDate() { 
    var weekStartDate = new Date(nowYear, nowMonth, nowDay - nowDayOfWeek - 7); 
    return formatDate(weekStartDate); 
}

//获得上周的结束日期 
function getLastWeekEndDate() { 
    var weekEndDate = new Date(nowYear, nowMonth, nowDay - nowDayOfWeek - 1); 
    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); 
}

//获得上月开始时间 
function getLastMonthStartDate() { 
    if(lastMonth==11){ 
        var lastMonthStartDate = new Date(nowYear-1, lastMonth, 1); 
    }else{ 
        var lastMonthStartDate = new Date(nowYear, lastMonth, 1); 
    } 
    return formatDate(lastMonthStartDate); 
} 

//获得上月结束时间 
function getLastMonthEndDate() { 
    if(lastMonth==11){ 
        var lastMonthEndDate = new Date(nowYear-1, lastMonth, getMonthDays(lastMonth)); 
    }else{ 
        var lastMonthEndDate = new Date(nowYear, lastMonth, getMonthDays(lastMonth)); 
    } 
    return formatDate(lastMonthEndDate); 
}

//获得本季度的开始日期 
function getQuarterStartDate() { 
    var quarterStartDate = new Date(nowYear, getQuarterStartMonth(), 1); 
    return formatDate(quarterStartDate); 
} 

//获得本季度的结束日期 
function getQuarterEndDate() { 
    var quarterEndMonth = getQuarterStartMonth() + 2; 
    var quarterStartDate = new Date(nowYear, quarterEndMonth, getMonthDays(quarterEndMonth)); 
    return formatDate(quarterStartDate); 
}

结语

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