vue将获取到的时间转换格式

start_time() {
      const daterc = this.addRule.sending_rules.purchase_date_time[0];
      if (daterc != null) {
        var date = new Date(daterc);
        var year = date.getFullYear();
        /* 在日期格式中，月份是从0开始，11结束，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
         * */
        var month =
          date.getMonth() + 1 < 10 ? "0" + (date.getMonth() + 1): date.getMonth() + 1;
        var day = 
          date.getDate() < 10 ? "0" + date.getDate() : date.getDate();
        var hours =
          date.getHours() < 10 ? "0" + date.getHours() : date.getHours();
        var minutes =
          date.getMinutes() < 10 ? "0" + date.getMinutes() : date.getMinutes();
        var seconds =
          date.getSeconds() < 10 ? "0" + date.getSeconds() : date.getSeconds();
        // 拼接时间格式
        // year + "-" + month + "-" + day + " " + hours + ":" + minutes + ":" + seconds
        let timeList = year + "-" + month + "-" + day;
        this.addRule.sending_rules.purchase_date_time[0] = timeList;
        console.log(timeList, "timeList");
        // return timeList;
      }
    },