componentDidMount() {

        const _self = this; // 指向本對象的指針

        var myDate = new Date();
        document.getElementsByClassName('year')[0].innerHTML = myDate.getFullYear();

        var month = myDate.getMonth()+1;
        month =(month<10 ? "0"+month:month);

        document.getElementsByClassName('month')[0].innerHTML = month; // 月份自動加0

        var day = myDate.getDate();
        day =(day<10 ? "0"+day:day);

        document.getElementsByClassName('day')[0].innerHTML = day; // 日子自動加0;

        var hour = myDate.getHours();
        hour =(hour<10 ? "0"+hour:hour);

        document.getElementsByClassName('hour')[0].innerHTML = hour; // 小時自動加0

        var minute = myDate.getMinutes();
        minute =(minute<10 ? "0"+minute:minute);

        document.getElementsByClassName('minute')[0].innerHTML = minute; //獲取當前分鐘數(shù)(0-59)

        _self.showTimer = setInterval(()=> this.treat(), 1000*3); // 1分鐘換一次數(shù)據(jù)
    }