html
 

  <view class="countdown">  
    <text>倒计时：</text>  
    <text wx:for="{{countdown}}" wx:key="index">{{item}}</text>  
  </view>

ts
 

 data: {
    countdown: [], // 存放倒计时数组  
    targetTime: '', // 目标时间戳  
    intervalId: null, // 定时器ID 
}
startCountdown () {  
  const that = this;  
  // 每秒更新一次倒计时  
  this.data.intervalId = setInterval(function () {  
    const now = new Date().getTime();  
    const diff = that.data.targetTime - now;  
      
    if (diff <= 0) {  
      // 倒计时结束，清除定时器  
      clearInterval(that.data.intervalId);  
      that.setData({  
        countdown: ['倒计时结束'],  
      });  
    } else {  
      // 计算剩余的天、时、分、秒  
      const days = Math.floor(diff / (1000 * 60 * 60 * 24));  
      const hours = Math.floor((diff % (1000 * 60 * 60 * 24)) / (1000 * 60 * 60));  
      const minutes = Math.floor((diff % (1000 * 60 * 60)) / (1000 * 60));  
      const seconds = Math.floor((diff % (1000 * 60)) / 1000);  
        
      that.setData({  
        countdown: [days, '天', hours, '时', minutes, '分', seconds, '秒'],  
      });  
    }  
  }, 1000);     
  },
  onLoad: function (options) {   
  this.setData({  
    targetTime: new Date('2024-04-28 16:53:10').getTime(),  
  });  
  this.startCountdown();  


}