Use a variable in many components Angular

Question

I have this function to get the time the user is authenticated and it is running on the login button if the data entered is valid. I wanted to use that "this.time" in many different components of the application to show the user authentication time, but I don't know how to do that since the value of "this.time" is not static, could someone help me please? How do I get that value to other components?

  public sec = 0;
  public min = 0;
  public hour = 0;
  public time: string;      

startStopWatch() {
    this.time = "00:00:00";
    setInterval(() => {
      console.log(this.time)
      this.sec++;
      this.time = (this.hour + ':' + this.min + ':' + this.sec);
      if (this.sec === 60) {
        this.min++;
        this.sec = 0;
        if (this.min === 60) {
          this.hour++;
          this.min = 0;
        }
      }
    }, 1000);
  }

Answer 1

You can make all this accessible through a service, and, since it looks like this is all related to authentication, you can make a nice AuthService. I have provided example code that will provide the functionality you are looking for.

In the authService, @Injectable({ providedIn: "root" }) will make this service have global scope, so any component will have access. I have provided an example component that shows you how to use that authService and get the timer info.

Hope this helps!

auth.service.ts

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

@Injectable({ providedIn: "root" })
export class AuthService {

  private isAuth: boolean;

  private sec = 0;
  private min = 0;
  private hour = 0;
  private time: string;      


  constructor() {}

  public login(){
    /* authentication logic here
    
    If authenticated, then this.startStopWatch()
    
    */
  }

  private startStopWatch() {
      this.time = "00:00:00";
      setInterval(() => {
        console.log(this.time)
        this.sec++;
        this.time = (this.hour + ':' + this.min + ':' + this.sec);
        if (this.sec === 60) {
          this.min++;
          this.sec = 0;
          if (this.min === 60) {
            this.hour++;
            this.min = 0;
          }
        }
      }, 1000);
    }

  public getTimer(){
    return this.time;
  }

}

Example Component

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

@Component({
  selector: 'app-test',
  templateUrl: './test.component.html',
  styleUrls: ['./test.component.scss']
})
export class TestComponent{

  constructor(private authService: AuthService) { }

  testFunction(){

    console.log(this.authService.getTimer())

  }

}