datepicker-config.ts

import {Component} from '@angular/core';
import {
  NgbCalendar,
  NgbDate,
  NgbDateStruct,
  NgbInputDatepickerConfig
} from '@ng-bootstrap/ng-bootstrap';

@Component({
  selector: 'ngbd-datepicker-config',
  templateUrl: './datepicker-config.html',
  providers: [NgbInputDatepickerConfig] // add config to the component providers
})
export class NgbdDatepickerConfig {

  model: NgbDateStruct;

  constructor(config: NgbInputDatepickerConfig, calendar: NgbCalendar) {
    // customize default values of datepickers used by this component tree
    config.minDate = {year: 1900, month: 1, day: 1};
    config.maxDate = {year: 2099, month: 12, day: 31};

    // days that don't belong to current month are not visible
    config.outsideDays = 'hidden';

    // weekends are disabled
    config.markDisabled = (date: NgbDate) => calendar.getWeekday(date) >= 6;

    // setting datepicker popup to close only on click outside
    config.autoClose = 'outside';

    // setting datepicker popup to open above the input
    config.placement = ['top-left', 'top-right'];
  }
}