What Not to Miss in Angular 18: New Features and Updates

Key Takeaways:

Table of Contents

Introduction

The Angular framework keeps getting better with every major release. Angular 18, the next big update, promises thrilling new features and enhancements to make the development experience even more effective, delightful, and highly productive.

The Angular team has constantly tried to address the pain points and feedback from the developer community, which resulted in critical updates in the latest– Angular v18. It has significantly focused on improving performance, better routing, and optimizing developer tools to streamline the development process.

What’s New in Angular 18? Key Features and Updates

Angular 18 is the latest version in the ecosystem, with multiple improvements and new advanced features. It prioritizes enhancing existing strengths and executing performance optimization. Let’s dive into the critical subject of this guide and look at the latest features of Angular v18.

1. Zoneless application

The star update in the Angular 18 features is zoneless change detection. Previously, a library named Zone.js acted as a middleman, ensuring smooth operation. Traditionally, Angular relied on Zone.js to detect changes within your application. While Zone.js offered smooth operation, it also had drawbacks like increased development complexity and performance overhead.

However, Angular 18 introduces an experimental new feature called “zoneless change detection.” Zoneless change detection aims to remove the dependency on Zone.js (using signals is optional), providing benefits like:

• Smaller bundle size: Eliminating Zone.js can lead to a leaner application with faster loading times.
• Enhanced performance: The change of direction will be faster than the traditional approach.
• Simpler debugging: Removing Zone.js, stack traces become more readable and easier to analyze.
• Better core web vitals: Zoneless applications could perform better regarding web page load metrics and offer better ecosystem compatibility.

Coalescing by default

Angular uses the same scheduler for zoneless apps with coalescing enabled. However, to decrease the change detection cycles in the new Zone.js apps, Angular introduced Zone coalescing by default.

Moreover, it only applies to new applications because it can cause bugs in the previous change detection behavior. Coalescing also decreases unnecessary change detection cycles and improves performance for a few applications.

You can try the experimental zoneless support in Angular 18 by adding provideExperimentalZonelessChangeDetection to your app bootstrap:

After you add the provider, remove zone.js from your polyfills in angular.json. You can also add zoneless in your components using the following signals.

Furthermore, check the requirements for Zoneless compatibility for your Angular application:
☑ ChangeDetectorRef.markForCheck (known automatically by AsyncPipe)
☑ ComponentRef.setInput
☑ Updating a signal, which read in a template
☑ Bound host or template listen to callbacks
☑ Adding a view marked dirty by one of the above

Note: Also, Zoneless is compatible with your Angular if components can run ChangeDetectionStrategy.OnPush.

2. New RedirectCommand

Another navigation powerhouse introduced in Angular 18 to simplify the process is the RedirectCommand. It allows developers to develop smoother, dynamic navigation to streamline user experience within their Angular application. Moreover, the RedirectCommand class can manage complex navigation and patterns with Guards and Resolvers.

It also allows the class to simplify routing problems and provide a straightforward redirection method. With the command, you control redirects, such as keeping track of extra clues like query parameters and avoiding specific actions like updating location history.

For instance, consider redirecting functions as a multipurpose tool that helps you with various redirecting needs across your Angular application. As a result, it empowers developers to create clean, efficient, and user-friendly navigation experiences within applications.

3. TypeScript 5.4 Support

This new version of Angular allows you to take full advantage of the new TypeScript – TypeScript 5.4. It adopts new language features and type safety. Also, it improves code maintainability, readability, and overall enhancement that enhances performance.

It enables you to use the latest improvements and features of the TypeScript language in your Angular projects.

The highlight of this feature is –

• Improved readonly support: It will work on readonly properties, making it more secure and consistent using the readonly keyword. It assists developers in availing security benefits and making effects reliable with precise type definitions.
• Template literal types: It allows you to define types of templates precisely and helps developers to catch errors easily. Moreover, it highlights the precise types for string literals so that you can spot mistakes during the development time.
• New import types: It helps to make code more organized and modular.

Note: Update your tsconfig.json: Verify that the compilerOptions in your tsconfig.json file are compatible with TypeScript 5.4.

4. Routes Redirect as a Function

Another significant feature of Angular 18 is the routes redirect, where developers can manage the redirect function seamlessly. In this new Angular version, developers can replace strings with specific functions to redirect URLs within the redirectTo property of the Route object. As a result, it boosts routing flexibility and brings new possibilities.

It also contains URLTree, a tool that simplifies website navigation for users and developers. It includes a web address (URL) and breaks it into primary elements, such as vital information, title, routing, page name, and query.

In addition, UrlTree in Angular 18 plays a crucial role in security, helps you control certain pages, and ensures a smooth navigation experience within the Angular application.

Need to redirect to a route based on runtime state? You can implement advanced logic in a function to handle this seamlessly:

Note: Route.redirectTo supports a string or a function.

5. Improved Reactivity Model

The reactivity model in Angular v18 makes data flow and state management easier. It is more intuitive and decreases boilerplate code, which helps handle complex state interactions. Another plus point is that it improves performance by optimizing change detection mechanisms.

For instance, using an improved reactivity model, you can update the function whenever the change is required, providing a faster and more engaging user experience.

6. Default Content for ng-content

In the latest version of Angular, you can add default content with the ng-content tag. This directive creates a placeholder in the component template where the content can be inserted dynamically.

Moreover, the new ng-template API makes creating and utilizing templates easier. With its ability, you can use reusable templates and maintain them efficiently. Also, if the tag already exists in the content, it will follow the default content. The newly added feature is a logical extension of the ng-content.

You can use the following content for the result-

Which will result in the

7. Unified Control State Changes Event

The FormControl, FormGroup, and FormArray classes from Angular forms now uncover a potent new property called events. It enables you to subscribe to a stream of events for any form of control. The state changes event helps you track changes in value, touch state, and control status.

Consequently, it gives more control over the form validation process with easily defined form objects and rules like declarative or asynchronous validation support. Moreover, new forms of API can manage more complex validation methods, improve reactivity, and handle errors more easily.

Now, you can utilize this to form control:

8. Event Replay

Another thing that kicks up the buzz of Angular 18 is the event replay feature—event dispatch, earlier known as jsaction, which is now part of Angular Monorepo. Event replay is helpful during scenarios where user events occur before the page is fully interactive.

Let’s take an example of a website where you can click a like button on a funny video, but your internet works slowly. Traditionally, the click would not register until the video loaded. However, with this new feature of Angular v18, the website can remember your likes despite network or loading conditions.

The event replay feature is now available in v18 in the developer preview. You can use withEventReplay(), for example:

9. Stable Improvements

Material 13, built-in control flow, and deferrable view were highlights of Angular v17 and gained popularity among developers. However, in Angular version 18, all are stable and efficient.

❖ Material 3
The Angular team used developers’ feedback to polish the Material component. Thus, they introduced its stable version in Angular 18 with a new Material 3 theme and design documentation within Angular.

You can also seek its guide for the Angular 18 tutorial of Material 3.

❖ Deferrable view
Deferrable views were introduced in V17 to improve performance. However, it is no longer in the experimental stage and was announced as stable by the Angular team after addressing community feedback and significant changes.

Using the deferrable view, you can enhance perceived performance by showing users the essential content while other sections load in the background, resulting in seamless UX. Moreover, using @defer, you can decrease bundle size and incorporate it into your applications and libraries.

❖ Built-in control flow
Control Flow syntax is no longer in developer preview status; it’s now stable. The Angular developer team has announced the new built-in control flow, which includes the new syntax adoption and enhanced performance.

In the updated built-in control flow, Angular has improved its control flow’s type checking, set guardrails for specific performance-related antipatterns, and allowed more implicit variables.

10. Announcement of Angular.dev

Yet another exciting new notification in Angular 18 is for the developer community. Angular has disclosed Angular. dev, an official documentation website for Angular coders. It has an upgraded modern look and feels like you find an interactive, hands-on tutorial based on multiple topics. Whether it is WebContainers or simple navigation, the Angular team has ensured all essential information is covered.

Moreover, all requests to Angular.io are automatically redirected to Angular. Dev.

11. Partial Hydration

Yet another significant new feature of Angular 18 is partial hydration. This technique hydrates your app after server-side rendering (essential parts only), indicating less JavaScript loading. As a result, the rest loads on JavaScript upfront, resulting in improved performance.

Moreover, it simplifies complex components, like calendars, and only loads when needed. Only the main content appears first; other sections load when you click on them. This is partial hydration in action.

In addition, the Angular community team is working on prototyping partial hydration and interactively triggers the importance of data triggers like components that change binding values.

12. Firebase App Hosting Enhancement

Hosting your application has become crucial because web platforms are becoming increasingly complex in performance, productivity, reliability, and scalability. Apps with hybrid rendering, including client-side rendering, pretending, and server-side rendering, have different hosting needs. As a result, Firebase app hosting is initiated to manage all developers’ requirements.

Firebase App Hosting was announced at Google I/O and has been developed in collaboration with Angular to ensure a smooth developer experience.

The Firebase app hosting streamlines the development and deployment of Angular apps. It has built-in framework support, is easily deployed with GitHub integration, and works well with Firebase products like Authentication, Cloud Firestore, and Vertex AI for Firebase.

What’s More Enhanced in Angular 18?

Angular 18 also has improved existing features, components, and functionalities to deliver the best for Angular development.

? Server-side Rendering Improvements
Angular 18 enhances SSR for rapid performance and seamless experience. It includes pre-rendering capabilities, faster server-side hydration, and great Angular Universal support. Moreover, it has improved the hydration of i18n blocks by collaborating with the Chrome Auora team; however, it is in developer preview mode. Hence, with server-side rendering improvements, there has been a responsive user experience and faster response to slower networks.

? Single APIs
In Angular v17, the team declared new single inputs, output syntax, and single-based queries. To improve the latest version, the Angular team is converting it to stable for quick results.

? Angular CLI
The Angular CLI is here to improve the development process. Earlier, it was announced as stable in Angular version 17, but to update the experience, Angular experts have built a new experience and received an edit/refresh boost. You can find the updated guide to automate new experiences. Additionally, it uses Vite with esbuild to replace the traditional webpack experience. Since webpack dependency is optional, the Angular CLI speeds up, and its installment time has been reduced by 50%.

? Standalone Components
Another upgraded element in Angular v18 is the standalone component. As previous components no longer require NgModules, this helps simplify the architecture and facilitate reusable components across your Angular application. It also decreases the overhead associated with module management.

? Debugging Experience
The Angular community updated Angular DevTools to visualize Angular’s hydration process. You will find an icon representing the component’s hydration status. Moreover, you can overlay mode to check which components Angular hydrated on the page. If there are errors in your app, Angular DevTools will preview them through Component Explorer.

How Can You Upgrade Angular v17 to Angular v18?

Below is the checklist you need to follow and consider while upgrading your Angular project.

➢Before you update:
No changes are required while moving between the Angular 17 and 18 versions.

➢While updating the new version:
You must check these changes and take the following actions to update your application.

• Ensure you use a supported Node js version before upgrading your application. Angular v18 supports Node.js versions v18.19.0 and newer.
• In the application’s project directory, operate ng update @angular/core@18 @angular/cli@18 to upgrade your application to Angular v18.
• Update TypeScript to version 5.4 or newer.

➢After you update:
There is no need to do anything after moving between these versions.

Conclusion