传入一个已经过去了的时间点的时间戳,返回 '刚刚','几分钟前','几小时前','几天前','几周前','几月前

/**
 * 传入一个已经过去了的时间点的时间戳13位[毫秒](也就是时间戳小于当前时间的时间戳)
 * 返回 '刚刚','几分钟前','几小时前','几天前','几周前','几月前' 如果大于月的话就会显示为几年几月几日(2015-02-26)
 * eg:  var zhi = timeago('1424966376000'); 返回的zhi就可以显示到页面了
 */
function timeago (dateTimeStamp) {
    var minute = 1000 * 60;      //把分，时，天，周，半个月，一个月用毫秒表示
    var hour = minute * 60;
    var day = hour * 24;
    var week = day * 7;
    var month = day * 30;
    var now = new Date().getTime();   //获取当前时间毫秒
    var diffValue = now - dateTimeStamp;//时间差

    if (diffValue < 0) {
        return '传入的时间戳大于当前时间戳';
    }
    var minC = diffValue / minute;  //计算时间差的分，时，天，周，月
    var hourC = diffValue / hour;
    var dayC = diffValue / day;
    var weekC = diffValue / week;
    var monthC = diffValue / month;
    if (monthC >= 1 && monthC <= 3) {
        result = " " + parseInt(monthC) + "月前"
    } else if (weekC >= 1 && weekC <= 3) {
        result = " " + parseInt(weekC) + "周前"
    } else if (dayC >= 1 && dayC <= 6) {
        result = " " + parseInt(dayC) + "天前"
    } else if (hourC >= 1 && hourC <= 23) {
        result = " " + parseInt(hourC) + "小时前"
    } else if (minC >= 1 && minC <= 59) {
        result = " " + parseInt(minC) + "分钟前"
    } else if (diffValue >= 0 && diffValue <= minute) {
        result = "刚刚"
    } else {
        var datetime = new Date();
        datetime.setTime(dateTimeStamp);
        var Nyear = datetime.getFullYear();
        var Nmonth = datetime.getMonth() + 1 < 10 ? "0" + (datetime.getMonth() + 1) : datetime.getMonth() + 1;
        var Ndate = datetime.getDate() < 10 ? "0" + datetime.getDate() : datetime.getDate();
        var Nhour = datetime.getHours() < 10 ? "0" + datetime.getHours() : datetime.getHours();
        var Nminute = datetime.getMinutes() < 10 ? "0" + datetime.getMinutes() : datetime.getMinutes();
        var Nsecond = datetime.getSeconds() < 10 ? "0" + datetime.getSeconds() : datetime.getSeconds();
        //这里如果需要精确到时分秒可以加上(这里我没有加)
        result = Nyear + "-" + Nmonth + "-" + Ndate
    }
    return result;
}