SOURCE

new Vue({
    el: "#example",
    filters: {
        formatTimestampToDate(val) {
            let temp = new Date(val)
            return `${temp.getFullYear()}-${temp.getMonth()+1}-${temp.getDate()} 星期${temp.getDay()}`
        }
    },
    data: {
        curDay: new Date().getTime(),
        count: 0
    },
    computed: {
        day() {
            return this.curDay + (this.count * 24 * 3600 * 1000)
        }
    },
    methods: {
        addOneDay() {
            this.count++
        }
    },
    watch: {
        day: function(newValue, oldValue) {
            console.log("this.day === newValue",this.day === newValue)
            console.log(`newValue:${newValue},oldValue:${oldValue}`)
        }
    },
    filters: {
        formatTimestampToDate(val) {
            let temp = new Date(val)
            return `${temp.getFullYear()}-${temp.getMonth()+1}-${temp.getDate()} 星期${temp.getDay()}`
        }
    },
    template: `<div>
    <div>日期：{{ day | formatTimestampToDate }}</div>
	<button type="button" @click="addOneDay">add one day</button>
	</div>
    `
})

<div id="example"></div>