倒计时： 
   {{countDownHour}} : 
   {{countDownMinute}} : 
   {{countDownSecond}}
 

const formatTime = date => {
 
   const year = date.getFullYear()
   const month = date.getMonth() + 1
   const day = date.getDate()
   const hour = date.getHours()
   const minute = date.getMinutes()
   const second = date.getSeconds()
 
   return [year, month, day].map(formatNumber).join('/') + ' ' + [hour, minute, second].map(formatNumber).join(':')
 
}
 
const formatNumber = n => {
   n = n.toString()
   return n[1] ? n : '0' + n
}
 
module.exports = {
   formatTime: formatTime
}

var util = require('../../utils/util.js');    //调用微信小程序中时间格式化的js
 
Page: ({
 
    data: {
 
         countDownHour: 0, //倒计时 -时
         countDownMinute: 0, //倒计时 -分
         countDownSecond: 0, //倒计时-秒
 
     },
 
 
 
    // 页面渲染后 执行
 
    onLoad: function () {
 
        //设置倒计时时间，1s变换一次
        var interval = setInterval(function () {
           var d = new Date();  //获取系统日期和时间
           var nowHour = d.getHours(); //小时
           var nowMinutes = d.getMinutes(); //分
           var nowSeconds = d.getSeconds(); //秒
 
           // 显示在倒计时中的小时位
           var hour = 24 - nowHour;
 
           // 显示在倒计时中的分钟位
           var minutes = 60 - nowMinutes;
 
           // 显示在倒计时中的秒数
           var seconds = 60 - nowSeconds;
 
 
           //当小时、分钟、秒都为0时，活动结束，倒计时显示为00:00:00
           if (hour == 0 && minutes == 0 && seconds == 0) {
 
              clearInterval(interval);
              wx.showToast({
                title: '活动已结束',
              });
              console.log(totalSecond);
 
              this.setData({
                countDownHour: '00',
                countDownMinute: '00',
                countDownSecond: '00',
              });
           }
 
 
           //当小时位、分钟位、秒位小于10时，用字符串拼接的方式显示，例如：06:08:02
 
           if (hour < 10) {
             hour = "0" + hour;
           }
           if (minutes < 10) {
             minutes = "0" + minutes;
           }
           if (seconds < 10) {
             seconds = "0" + seconds;
           }
           this.setData({
             countDownHour: hour,
             countDownMinute: minutes,
             countDownSecond: seconds,
           });
        }.bind(this), 1000);
   },
})