jq日期-小方法（时间戳转换，毫秒转换）

 //比较日期大小
    function compareDate(checkStartDate, checkEndDate) {
        var arys1= new Array();
        var arys2= new Array();
        if(checkStartDate != null && checkEndDate != null) {
            arys1=checkStartDate.split('-');
            var sdate=new Date(arys1[0],parseInt(arys1[1]-1),arys1[2]);
            arys2=checkEndDate.split('-');
            var edate=new Date(arys2[0],parseInt(arys2[1]-1),arys2[2]);
            if(sdate < edate) {
                return true;
            }  else {
                layer.alert("证件有效期起应小于证件有效期止");
                return false;

            }
        }
    }

　　

  // 日期格式化 时间戳
    function timestampToTime(timestamp) {
        var date = new Date(timestamp);
        Y = date.getFullYear() + '-';
        M = (date.getMonth() + 1 < 10 ? '0' + (date.getMonth() + 1) : date.getMonth() + 1) + '-';
        D = (date.getDate() < 10 ? '0' + (date.getDate()) : date.getDate()) + ' ';
        h = (date.getHours() < 10 ? '0' + (date.getHours()) : date.getHours()) + ':';
        m = (date.getMinutes() < 10 ? '0' + (date.getMinutes()) : date.getMinutes()) + ':';
        s = (date.getSeconds() < 10 ? '0' + (date.getSeconds()) : date.getSeconds());
        return Y + M + D + h + m + s;
    }

 //时间转换-毫秒转时分秒
    function MillisecondToDate(msd) {
        var times = parseFloat(msd) / 1000;
        if (null != times && "" != times) {
            times = parseInt(times / 3600.0) + "时" + parseInt((parseFloat(times / 3600.0) -
                parseInt(times / 3600.0)) * 60) + "分" +
                parseInt((parseFloat((parseFloat(times / 3600.0) - parseInt(times / 3600.0)) * 60) -
                    parseInt((parseFloat(times / 3600.0) - parseInt(times / 3600.0)) * 60)) * 60) + "秒";
        }
        console.log(times)
        return times;
    }

// 补零
            fixZero(num,length){
                var str=""+num;
                var len=str.length;    
                var s="";
                for(var i=length;i-->len;){
                    s+="0";
                }
                return s+str;
            }

倒计时
 countTime() {
                let date = new Date();
                let now = date.getTime();
                let start = that.objectArray.createTime;
                // 计算开始时间
                let startDate = new Date(start.replace(/-/g, '/'));
                //计算订单截止时间
                let endDate = startDate.getTime() + 1800000;//时间差
                // 下单时间已超出30分钟
                let lifetime = endDate - now;
                if (lifetime <= 0) {
                    that.isActualStock = true;
                    that.countdownArr.countdown = '00:00:00';
                    return false;
                }//未超出
                that.countdownArr.lifetime = that.countdownArr.lifetime - 1000;
                //定义变量 d,h,m,s保存倒计时的时间
                if (that.countdownArr.lifetime >= 0) {
                    let h = Math.floor(that.countdownArr.lifetime / 1000 / 60 / 60 % 24);
                    let m = Math.floor(that.countdownArr.lifetime / 1000 / 60 % 60);
                    let s = Math.floor(that.countdownArr.lifetime / 1000 % 60);
                    that.time.h = h < 10 ? '0' + h : h;
                    that.time.m = m < 10 ? '0' + m : m;
                    that.time.s = s < 10 ? '0' + s : s;
                }
                //递归每秒调用countTime方法，显示动态时间效果
                this.countdownArr.countdown = that.time.h + ':' + that.time.m + ':' + that.time.s
                setTimeout(that.countTime, 1000);
            }