How async and await work in Angular 15?

How async and await work in Angular 15?

Here is a detailed explanation of how async and await work in Angular 15.

The async keyword is used to define an asynchronous function, which is a function that returns a promise. Async functions make it easy to work with asynchronous code, as they allow you to use the await keyword to wait for a promise to be resolved.

Here is an example of an async function:

async function getData() {
  try {
    const data = await someAsyncTask();
    return data;
  } catch (error) {
    console.error(error);
  }
}

The await keyword can only be used inside an async function, and it causes the function to pause execution until the promise is resolved. In the example above, the function will pause at the await line until someAsyncTask() is complete, and then the resolved value of the promise will be stored in the data variable.

Here is an example of how you might use an async function in an Angular 15 component:

import { Component, OnInit } from '@angular/core';
import { HttpClient } from '@angular/common/http';

@Component({
  selector: 'app-my-component',
  templateUrl: './my-component.component.html',
  styleUrls: ['./my-component.component.css']
})
export class MyComponentComponent implements OnInit {
  data: any;

  constructor(private http: HttpClient) { }

  ngOnInit() {
    this.getData();
  }

  async getData() {
    try {
      this.data = await this.http.get('/api/data').toPromise();
    } catch (error) {
      console.error(error);
    }
  }
}

In this example, the getData() function is an async function that makes an HTTP GET request using the Angular HttpClient. The await keyword is used to wait for the HTTP request to complete, and the resolved value of the promise (the data returned by the server) is stored in the data property of the component.