How to show current time in angular without using setInterval()

Question

I want to show current active time in angular 11.

I did like this

   setInterval(() => {
      this.UKTime = formatDate(
        Date.now(),
        "dd-MM-yy hh:mm a",
        "en-US",
        "+0100"
      );
      this.SLTime = formatDate(
        Date.now(),
        "dd-MM-yy hh:mm a",
        "en-US",
        "+0530"
      );
    }, 1000);

But I do not need timer.

Is there any other way to show current time?

Answer 1

app.component.ts

export class AppComponent implements OnInit, OnDestroy {
  rxTime = new Date();
  intervalId;
  subscription: Subscription;

  ngOnInit() {

    // Using RxJS Timer
    this.subscription = timer(0, 1000)
      .pipe(
        map(() => new Date()),
        share()
      )
      .subscribe(time => {
        let hour = this.rxTime.getHours();
        let minuts = this.rxTime.getMinutes();
        let seconds = this.rxTime.getSeconds();
        //let a = time.toLocaleString('en-US', { hour: 'numeric', hour12: true });
        let NewTime = hour + ":" + minuts + ":" + seconds
        console.log(NewTime);
        this.rxTime = time;
      });
  }

  ngOnDestroy() {
    clearInterval(this.intervalId);
    if (this.subscription) {
      this.subscription.unsubscribe();
    }
  }
}

app.component.html

RxJS Clock:
<div>{{ rxTime | date: 'hh:mm:ss a' }}</div>

Working Demo