js获取本月，本季度，上个季度，本周，上周的起始和结束时间

/* 获得某月的天数 */
    function getMonthDays(myMonth) {
        var nowYear = new Date().getFullYear(); //当前年
        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;
    }

    /* 获得本周的开始日期 */
    function getWeekStartDate() {
        var now = new Date();
        var nowYear = now.getFullYear(); //当前年
        var nowMonth = now.getMonth();
        var nowDay = now.getDate();
        var nowDayOfWeek = now.getDay(); //今天本周的第几天
        var day = nowDay - nowDayOfWeek;
        console.log("getWeekStartDate:nowYear=" + nowYear + ",nowMonth=" + nowMonth + ",nowDay=" + nowDay + ",nowDayOfWeek=" + nowDayOfWeek + ",day=" + day);
        console.log("getWeekStartDate：" + new Date(nowYear, nowMonth, day));
        return new Date(nowYear, nowMonth, day);
    }

    /* 获得本周的结束日期 */
    function getWeekEndDate() {
        var now = new Date();
        var nowYear = now.getFullYear(); //当前年
        var nowMonth = now.getMonth();
        var nowDay = now.getDate();
        var nowDayOfWeek = now.getDay(); //今天本周的第几天
        var day = nowDay + (6 - nowDayOfWeek);
        console.log("getWeekEndDate:nowYear=" + nowYear + ",nowMonth=" + nowMonth + ",nowDay=" + nowDay + ",nowDayOfWeek=" + nowDayOfWeek + ",day=" + day);
        console.log("getWeekEndDate：" + new Date(nowYear, nowMonth, day));
        return new Date(nowYear, nowMonth, day);
    }

    /* 获得上周的开始日期 */
    function getLastWeekStartDate() {
        var now = new Date();
        var nowYear = now.getFullYear(); //当前年
        var nowMonth = now.getMonth();
        var nowDay = now.getDate();
        var nowDayOfWeek = now.getDay(); //今天本周的第几天
        return new Date(nowYear, nowMonth, nowDay - nowDayOfWeek - 7);
    }

    /* 获得上周的结束日期 */
    function getLastWeekEndDate() {
        var now = new Date();
        var nowYear = now.getFullYear(); //当前年
        var nowMonth = now.getMonth();
        var nowDay = now.getDate();
        var nowDayOfWeek = now.getDay(); //今天本周的第几天
        return new Date(nowYear, nowMonth, nowDay - nowDayOfWeek - 1);
    }
    /* 获得本月的开始日期 */
    function getMonthStartDate() {
        var now = new Date();
        var nowYear = now.getFullYear(); //当前年
        var nowMonth = now.getMonth();
        return new Date(nowYear, nowMonth, 1);
    }

    /* 获得本月的结束日期 */
    function getMonthEndDate() {
        var now = new Date();
        var nowYear = now.getFullYear(); //当前年
        var nowMonth = now.getMonth();
        return new Date(nowYear, nowMonth, getMonthDays(nowMonth));
    }

    /* 获得上月开始时间 */
    function getLastMonthStartDate() {
        var lastMonthDate = new Date(); //上月日期
        lastMonthDate.setDate(1);
        lastMonthDate.setMonth(lastMonthDate.getMonth() - 1);
        return lastMonthDate;
    }
    /* 获得上月结束时间 */
    function getLastMonthEndDate() {
        var lastMonthDate = new Date(); //上月日期
        lastMonthDate.setMonth(lastMonthDate.getMonth() - 1);
        var lastMonth = lastMonthDate.getMonth();
        lastMonthDate.setDate(getMonthDays(lastMonth));
        return lastMonthDate;
    }

    /* 获得本季度的开始月份 */
    function getQuarterStartMonth() {
        var nowMonth = new Date().getMonth();
        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;
    }

    /* 获得本季度的开始日期 */
    function getQuarterStartDate() {
        var now = new Date();
        var nowYear = now.getFullYear(); //当前年
        return new Date(nowYear, getQuarterStartMonth(), 1);
    }
    /* 获得本季度的结束日期 */
    function getQuarterEndDate() {
        var now = new Date();
        var nowYear = now.getFullYear(); //当前年
        var quarterEndMonth = getQuarterStartMonth() + 2;
        return new Date(nowYear, quarterEndMonth, getMonthDays(quarterEndMonth));
    }

    /* 获得上个季度的开始日期 */
    function getLastQuarterStartDate() {
        var now = new Date();
        var nowYear = now.getFullYear(); //当前年
        return new Date(nowYear, getQuarterStartMonth() - 3, 1);
    }

    /* 获得上个季度的结束日期 */
    function getLastQuarterEndDate() {
        var quarterEndMonth = getQuarterStartMonth() - 1;
        var now = new Date();
        now.setMonth(quarterEndMonth);
        var nowMonth = now.getMonth();
        var nowYear = now.getFullYear();
        return new Date(nowYear, quarterEndMonth, getMonthDays(quarterEndMonth));
    }

UTC时间格式：

 2015-05-23T16:00:00.000Z

 

GMT时间格式：

 Sun May 24 2015 00:00:00 GMT+0800 (中国标准时间)