javaScript倒计时

//倒计时let timeinterval="";let countDownStart="";countDown(timeTotal) {timeinterval = setInterval(() => {    timeTotal--;    countDownStart = timeTotal + "秒";    if (timeTotal <= 0) {        clearInterval(this.timeinterval);        countDownStart = "倒计时开始";    }}, 1000);}countDown(60);