javascript - 连续获取之前、今天和明天的日期

Question

如何连续获取前一天？例如，我有这个 HTML:

<ul>
<li (click)="prevDay()"></li>
</ul>

<div>{{day}}</div>

JS:

dayBefore() {
        let now: any = new Date();
        this.days = ['Sunday','Monday','Tuesday','Wednesday','Thursday','Friday','Saturday'];
        this.day = this.days[now.getDay() - 1];
}

这样我只能得到昨天的数据，但我不断地需要它。当我再次点击<div>{{day}}</div>时我需要它在“昨天”的前一天等等。所以，星期四，星期三，星期二，等等......

编辑:今天和明天都一样......

Answer 1

在您的 Controller 中，仅初始化一次新日期数组

private myDate=new Date();
private days = ['Sunday','Monday','Tuesday','Wednesday','Thursday','Friday','Saturday'];
private day = this.days[this.myDate.getDay()];;

所以你今天有约会了。然后在更改日期的方法中更新您的日期。

private dayBefore(){
   this.myDate=this.myDate.addDays(-1);
   this.day= this.days[this.myDate.getDay()];
}

private dayAfter(){
   this.myDate=this.myDate.addDays(1);
   this.day= this.days[this.myDate.getDay()];
}

private restoreToday(){           
   this.myDate=new Date();
   this.day= this.days[this.myDate.getDay()];
}

并且，在您的 html 中

<ul>
   <li (click)="dayBefore()">Prev</li>
   <li (click)="restoreToday()">Today</li>
   <li (click)="dayAfter()">Next</li>
</ul>

<div>{{day}}</div>