Time CountDown in angular 2

Question

I want to have a date countdown like this:

http://codepen.io/garethdweaver/pen/eNpWBb

but in angular 2, I found this plunkr that adds 1 to a number each 500

Answer 1

Here's a solution i came up with recently on my project. It checks between a gate opening time of an event and the main event time of the same event. This uses Momentjs.

I have code in the onChanges function in case an event time changes in my firebase which is very unlikely, but i like the fact it can pick up on it and update on the fly.

Component:

import { Component, OnInit, Input, OnChanges } from '@angular/core';
import { Observable } from "rxjs/Rx"
import { RoundService } from '../../round.service'
import * as moment from 'moment-timezone';

@Component({
  selector: 'race-countdown',
  templateUrl: './race-countdown.component.html',
  styleUrls: ['./race-countdown.component.scss']
})
export class RaceCountdownComponent implements OnChanges,OnInit{

    @Input() activeRound;

    public time:number;
    public timeToGates:number;
    public timeToMains:number;  
    public countDown:Observable;
    public currentUnix = moment().unix();

    constructor(private rs:RoundService) { }

    ngOnChanges() {

    this.timeToGates = this.activeRound.gateOpenUnix - this.currentUnix;
    this.timeToMains = this.activeRound.mainEventUnix - this.currentUnix;

    if(this.timeToGates < 0)
        this.time = this.timeToMains
    else 
        this.time = this.timeToGates

  }

  ngOnInit() {

    this.countDown = Observable.interval(1000)
                                          .map(res=>{ return this.time = this.time-1 })
                                          .map(res=> {

                                            let timeLeft = moment.duration(res, 'seconds');
                                            let string:string = '';

                                            // Days.
                                            if(timeLeft.days() > 0) 
                                                string += timeLeft.days() + ' Days'

                                            // Hours.
                                            if(timeLeft.hours() > 0) 
                                                string += ' ' + timeLeft.hours() + ' Hours'

                                            // Minutes.
                                            if(timeLeft.minutes() > 0)
                                                string += ' ' + timeLeft.minutes() + ' Mins'

                                            // Seconds.
                                            string += ' ' + timeLeft.seconds(); 

                                            return string;

                                          })

  }

}

HTML:

{{countDown | async}}

Produces: '2 Days 6 Hours 59 Mins 42' etc