angular 5 input date component

datepicker.ts

import { Component, Input, OnInit, EventEmitter } from '@angular/core';

var template = `
    <input type="date" [ngModel]="now | date:'yyyy-MM-dd'"  (ngModelChange)="change($event)">
`
@Component({
  selector: 'date-picker',
  template: template,
  outputs: ['dateChange']
})
export class Datepicker implements OnInit{
  @Input() public now:Date;
  public dateChange = new EventEmitter()
  constructor(){}
  ngOnInit(){
    if(!(this.now instanceof Date)){
      this.now = new Date()
    }
  }

  change($event){
    let chooseDate = new Date($event)
    this.now = chooseDate
    this.dateChange.emit(chooseDate)
  }
}

demo.html

<date-picker [now]="defaultDate" (dateChange)="defaultDate = $event"></date-picker>