给一个时间实现倒计时

data() {
			return {
				seconds: 0,
				count: '',
				time: ''
			}
		},

mounted() {
			let that = this;
			var time = that.invoiceData.add_time || '';
			var strtime = time.replace(/-/g, '/')
			var date = new Date(strtime);
			that.time = date.getTime()
			console.log(that.time)
			console.log(that.aleartStatus)
			that.defaults()
		},
                	methods: {
			defaults() {
				this.Time() //调用定时器
				const timestamp = Date.parse(new Date());
				let time = new Date(this.time)
				let times = time.setHours(time.getHours() + 48)
				this.seconds = (times - timestamp) / 1000
			},
			countDown() {
				let d = parseInt(this.seconds / (24 * 60 * 60))
				d = d < 10 ? d : d
				let h = parseInt(this.seconds / (60 * 60) % 24);
				h = h < 10 ?  h : h
				let m = parseInt(this.seconds / 60 % 60);
				m = m < 10 ?  m : m
				let s = parseInt(this.seconds % 60);
				s = s < 10 ?  s : s
				
				if(d<=0&h<=0&m<=0&s<=0){
					this.count = '没有时间了'
					return
				}
				this.count = d + '天' + h + '时' + m + '分' + s + '秒'

			},
			Time() {
				setInterval(() => {
					this.seconds -= 1
					this.countDown()
				}, 1000)
			},
                        }

给一个时间和当前时间判断

```js
```	let date = res.data.pay_time * 1000
	let dates = new Date(date)
        let times = dates.setHours(dates.getHours() + 72)
	let sj = new Date(times)
        if (new Date() > sj) {
	
	}else{}