小程序支付倒计时demo

1. 时间格式化
   

   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
   }
   

   　　

2. 倒计时页面js
   

   1.引入格式化js
   import { formatTime } from '../../utils/util.js';
   
   2.data: {
       clock: ''  // wxml页面显示
     }
   
   3.触发倒计时时机，以onLoad为例：
       onLoad() { this.countDown() }
   
   4.倒计时函数
     countDown: function () {
       let that = this;
       // 1598274000000 == 2020-08-24 21:00:00；3480000ms == 58min == 3600000ms - 总支付时间
       let countDownNum = 1598274000000 - 2700000;
       let saveCountDownNum = 1598274000000 - 2700000;  // 保存初始时间
       that.setData({
         timer: setInterval(() => {
           countDownNum -= 1000;
           that.setData({
             clock: formatTime(new Date(countDownNum)).slice(14)  // 只保留分和秒
           })
           // 总支付时间：经过120000ms == 2min支付截至
           if (String(saveCountDownNum) - String(countDownNum) == 900000) {
             clearInterval(that.data.timer);
             wx.navigateBack({});
           }
         }, 1000)
       })
     }