<view >{{dateFormat(date)}}</view>

       data() {
      return {
        date: new Date().toISOString(),
      }
    },
      mounted() {
      let _this = this;
      setInterval(function() {
        _this.date = Date.parse(new Date());
      }, 1000);
    },
        methods: {
    dateFormat(time) {
        let date = new Date(time);
        let year = date.getFullYear();
        // 在日期格式中，月份是从0开始的，因此要加0，使用三元表达式在小于10的前面加0，以达到格式统一  如 09:11:05
        let month = date.getMonth() + 1 < 10 ? "0" + (date.getMonth() + 1) : date.getMonth() + 1;
        let day = date.getDate() < 10 ? "0" + date.getDate() : date.getDate();
        let hours = date.getHours() < 10 ? "0" + date.getHours() : date.getHours();
        let minutes = date.getMinutes() < 10 ? "0" + date.getMinutes() : date.getMinutes();
        let seconds = date.getSeconds() < 10 ? "0" + date.getSeconds() : date.getSeconds();
        // 拼接
        return year + "-" + month + "-" + day + " " + hours + ":" + minutes + ":" + seconds;
        // return year + "-" + month + "-" + day;
      }
}