Angular 16 Is Launch: Discover the Top 7 Features | Angular Developer

4 min readJun 23, 2023

Read Original Article :- https://softwaretechit.com/angular-16-is-launch-discover-the-top-7-features-angular-developer/

Angular released a major version upgrade, Angular 16, on May 3, 2023. As an Angular developer, I found this upgrade interesting since there were some significant improvements compared to the previous version.

So, in this article, I will discuss the top 7 features of Angular 16 to give you a better understanding.

1. Angular Signals

Angular Signals is the main feature developers have been waiting for since the Angular 16 roadmap was released. Although Solid.js inspired this concept, it is a whole new concept for Angular. It allows you to define reactive values and express dependencies between them. In other words, you can efficiently use Angular signals to manage state changes within Angular applications.

A signal can be recognized as a regular variable that users can synchronously access. But it comes with some additional features like notifying others (component templates, other signals, functions, etc.) of its value changes and creating a derived state in a declarative way.

import { Component, computed, effect, signal } from '@angular/core';
import { CommonModule } from '@angular/common';
import { bootstrapApplication } from '@angular/platform-browser';

@Component({
  selector: 'my-app',
  standalone: true,
  imports: [CommonModule],
  template: `
    <h1>Calculate Area</h1>
    <p>Answer : {{ area() }}</p>
    <button (click)="calculateArea(10,10)">Click</button>
  `,
})export class App {
    height = signal(5);
    width = signal(5);
    area = computed(() => this.height() * this.width());
    constructor() {
      effect(() => console.log('Value changed:', this.area()));
    }
    calculateArea(height: number, width: number) {
      this.height.set(height);
      this.width.set(width);
    }
}

In this example, I have created a computed value area and two signals named height and width. When the values of the signals are changed by invoking the calculateArea() function, the computed value will be updated and displayed in the template. Here is a working example for you to try it.

Although this looks fantastic, Angular has not abandoned zone.js and RxJS. Signals are an optional feature, and Angular will still work without them. Angular will gradually improve Signals in upcoming versions to make it a complete package.

2. Server-Side Rendering

The lack of server-side rendering (SSR) support was one of the most significant drawbacks of Angular compared to React. Angular 16 has resolved this issue with some significant improvements for server-side rendering.

Before, Angular used destructive hydration for SSR. In destructive hydration, the server first renders and loads the application to the browser. Then, when the client app gets downloaded and bootstrapped, it destroys the already rendered DOM and re-renders the client app from scratch. This approach caused significant UX issues, like screen flickering, and negatively impacted some Core Web Vitals such as LCP or CLS.anug.

Angular 16 introduces a new approach called non-destructive hydration to prevent these drawbacks. The DOM is not destroyed when the client app is downloaded and bootstrapped. It uses the same DOM while enriching it with client-side features like event listeners.

Non-destructive hydration is still at the developer preview stage. But you can enable it by adding provideClientHydration() as a provider when bootstrapping the application.

import {
 bootstrapApplication,
 provideClientHydration,
} from '@angular/platform-browser';

...bootstrapApplication(RootCmp, {
 providers: [provideClientHydration()]
});

According to the official Angular release note, this is just the beginning. They plan to explore partial hydration as the next step and work on several developer requests. You can find more about the Angular SSR development plan

3. Experimental Jest Support

Jest is one of the most-used testing frameworks among JavaScript developers. Angular has listened to developer requests and has introduced experimental Jest support with Angular 16.

All you have to do is install Jest using npm and update the angular.json file.

// Install jest
npm install jest --save-dev

// angular.json
{
  "projects": {
    "my-app": {
      "architect": {
        "test": {
          "builder": "@angular-devkit/build-angular:jest",
          "options": {
            "tsConfig": "tsconfig.spec.json",
            "polyfills": ["zone.js", "zone.js/testing"]
          }
        }
      }
   }
}

They plan to move all the existing Karma projects to Web Test Runner in future updates.