app.component.ts

import { Component } from '@angular/core';
import { WebSocketService } from './services/web-socket.service';

@Component({
  selector: 'app-root',
  templateUrl: './app.component.html',
  styleUrls: ['./app.component.css']
})
export class AppComponent {
  constructor(private _ws: WebSocketService) {
    this._ws.connect();
  }

  sendMessage() {
    this._ws.sendMessage();
  }
}