authentication.service.ts

import { Injectable } from '@angular/core';

@Injectable({
  providedIn: 'root'
})
export class AuthenticationService {

  constructor() { }

  authenticate(username,password){
    if(username==="cedric" && password==="cedric"){
      sessionStorage.setItem('authenticateuser',username)
      return true
    }
    else{
      return false
    }
  }

isUserLoggedIn(){
  let user = sessionStorage.getItem('authenticateduser');
  return !(user===null);
}

}