Angular 7 / Typescript根据创建的时间隐藏一个Div

Question

我有 div 元素，我想在它的创建时间超过 6 个月前隐藏它。如何在 typescript 和 angular 7 中实现这一点

AngularJS - hide/show div if date is within last 6 months

我曾这样尝试过，它会引发错误“DateConstructor”类型上不存在属性“getMonth” HTML：

 <div class="request"  *ngIf="request.createTime>six_month_before_date">
<!-Only then display data-->
</div>

打字稿

      public date = new Date() ;
  public six_month_before_date= this.date.setMonth(this.date.getMonth() -6); 


     private getRequestDuration(request) {
    let createdDate = new Date(request.createTime);
    let timeInMilliSeconds = this.currentDate.getTime() - 
     createdDate.getTime();
    let seconds = timeInMilliSeconds / 1000;
    let minutes = seconds / 60;
    let hours = minutes / 60 + 5; // FIXME: EST Offset
    hours = hours > 0 ? hours : 0; // FIXME: Hack to address time-stamp conversions / daylight savings time
    let days = hours / 24;
    return (days > 0 ? Math.floor(days) + ' days, ' : '') + Math.floor(hours % 24) + ' hours';
  }

Answer 1

问题与 TypeScript 和 Angular 本身无关，getMonth 方法不是静态的，因此无法通过其类名执行，需要使用实例：

private getRequestDuration(request) {
    let six_month_before_date = new Date();
    six_month_before_date.setMonth(six_month_before_date.getMonth() - 6);// minus six month
    ...
}

更新：您的问题可能的解决方案是：

HTML

<div class="request" *ngIf="createTime > six_month_before_date">

TypeScript

@Component({ ... })
export class YourClassComponent implements OnInit {
    ...
    createTime: Date;
    six_month_before_date: Date;

    ngOnInit() {
        const request = await doYourRequestHere();
        const duration = getRequestDuration(request); // Not being used now but may be needed somewhere else
        this.createTime = new Date(request.createTime);
        this.six_month_before_date = this.getSixMonthBeforeDate();
    }

    private getSixMonthBeforeDate() {
        const currentDate = new Date(); 
        currentDate.setMonth(currentDate.getMonth() - 6);
        return currentDate;
    }

    private getRequestDuration(request) {
        let createdDate = new Date(request.createTime);
        let timeInMilliSeconds = this.six_month_before_date.getTime() - 
        createdDate.getTime();
        let seconds = timeInMilliSeconds / 1000;
        let minutes = seconds / 60;
        let hours = minutes / 60 + 5; // FIXME: EST Offset
        hours = hours > 0 ? hours : 0; // FIXME: Hack to address time-stamp conversions / daylight savings time
        let days = hours / 24;
        return (days > 0 ? Math.floor(days) + ' days, ' : '') + Math.floor(hours % 24) + ' hours';
    }
}