Top 12 Angular Best Practices to Adapt in 2024 (Updated)

Angular is one of the most powerful JavaScript frameworks for building dynamic programming structures like web apps, native apps, and SPAs. Google’s intent behind releasing Angular 2 was to introduce a full-stack frontend JavaScript framework that was self-sufficient yet flexible enough to be integrated with any other popular JavaScript frameworks. By utilizing the various Angular tools while following some of the best practices in Angular will give your website/web app the best possible chance to shine amongst its competitors while providing the best user experience to your users.

Throughout the Angular App Development, I have got some new Angular practices which help in write clean code; maintain coding standard and performance.

One of the most important challenges of Angular, which you would know if you have used this framework before, is to be toes-to-toes with their quick updates and changes. As we all know, Angular released Angular 18 back on May 22, 2024. We have kept the latest Angular offerings in mind and integrated them into this best practices blog to get the most value for your time. Without further ado, let’s get right into it –

12 Angular Best Practices to follow in 2024

1. Angular Coding Best Practices using Angular Coding Styles
2. Single Responsibility Principle
3. Break the Large Components in Manageable Sizes
4. Make use of Angular CLI
5. Proper utilization of Lazy Loading
6. Utilizing ‘trackBy’ alongside ‘ngFOR’
7. Optimize Angular Files and Folders
   • File Naming
   • Class Naming
   • Folder Structure
   • Root Module
   • Feature Module
   • Shared Module
   • Core Module
8. Build Reusable Components
9. Use Index.ts
10. Avoid using Logic in the Component
11. Prevent Memory Leaks
    • Use of async pipe
    • Using ‘take(1)’
    • Using ‘takeUntill’
12. Always Document

1. Angular Coding Best Practices using Angular Coding Styles

One of the most important aspects to get right for any frontend JavaScript framework is gaining efficiency in its coding. Your code quality and code health play a significant role in deciding the effectiveness of your app. As a developer, you should always try to match Angular coding standards by following certain Angular coding styles. Developers often get overwhelmed and face difficulties fixing bugs and identifying immediate issues when dealing with complex code structures.

Here are some of the best coding rules for ensuring your Angular project complies with the standard Angular Style Guide –

• Make sure that the code does not exceed 400 lines limit per file.
• Ensure that the code does not exceed 75 lines for each function.
• If the variables have constant values, declare them with ‘const.’
• Name of properties and methods should be used in lower camel cases.
• Always leave an empty line between imports and modules.
• Don’t name the interfaces with starting uppercase ‘I’ as you would do in some programming languages.

2. Single Responsibility Principle

One of the most important practices in Angular development is to make sure that you don’t create more than one instance of any component, directive, or service inside the same file. Each file should only be responsible for one particular function. Doing this helps keep your Angular code – clean, manageable and readable, and maintainable.

3. Break the Large Components into Manageable Sizes

Just like you need to keep your code files clean and crisp, you should also practice the same habit for your components. Significant components can be tricky to test, debug and maintain. Your overall Angular app would benefit greatly with increased efficiency in breaking more significant components into smaller manageable ones. One of the Angular best practices is to try and break your components into smaller components to the extent that each has only one atomic task.

4. Make use of Angular CLI

# Install Angular CLI
npm install -g @angular/CLI
# Check Angular CLI version
ng version

Properly utilizing Angular CLI is one of the Angular best practices you cannot avoid. It is one of the most powerful tools for developing apps with Angular. Angular CLI is a command-line interface tool used for initializing, developing, scaffolding, maintaining, testing, and debugging Angular apps. You should use Angular CLI to build an initial-level structure for your overall application. Using Angular CLI makes it easier for other developers to understand the app flow and folder structure, saving a lot of development time.

Here are some of the essential commands to use with Angular CLI –

1. ng new – create an app that already works, out of the box.
2. ng generate – used for generating components, services, routes, and pipes with test shells.
3. ng serve – helps to test your app locally when developing.
4. ng test – for running various Angular tests on your app.
5. ng lint – helps your Angular code shine.
6. ng add @angular/PWA – helps in setting up the Angular service worker.

5. Proper utilization of Lazy Loading

Utilizing lazy load the modules can enhance your productivity. Lazy Load is a built-in feature in Angular which helps developers with loading the thing which is required. For example, when you use the feature, it loads the components and other things you needed and stops other and unnecessary files to get loaded. Here’s how it functions;

// app.routing.ts
{ path: 'not-lazy-loaded', component: NotLazyLoadedComponent }

Here the ‘LazyLoading‘ is not in place and you will end creating large and unnecessarily heavy-sized applications.

When you use;

You have used 'LazyLoad' and it helps you reduce the size of the application by abstaining from unnecessary file from loading.

6. Utilizing ‘trackBy’ alongside ‘ngFOR’

Using 'ngFor' allows Angular developers to re-render the entire DOM tree after any change in the array. This helps Angular make DOM changes specific to that defined array in place of re-rendering the entire DOM. Re-rendering the entire DOM places an unnecessary load on the resources and takes more time than using ‘trackBy,' which allows you to specify the changes separately.

When you use ‘ngFor’ such as;

Now, each time the changes occur, the whole DOM tree will be re-rendered.

When you use 'trackBy' functions, such as;

7. Optimize Angular Files and Folders

It is very important to organize and optimize your Angular folders for easy maintainability, readability, and accessibility to any content at a simple glance. Consistency is very important for the overall success of your Angular project. Here are some of the Angular folder best practices to neaten up your Angular resources –

7.1 File Naming

As per Angular file naming convention, here are the two things you need to keep in mind –

1. The name of your files and folders should convey their purpose.
2. Be consistent with the naming pattern that is –file features.filetype. (For instance, consultation.component.ts, auth.servce.ts, component.html.
3. If you want to add more descriptive tags to your file names, use (-) for separating the word in the name – tc-home.component.ts, book-appointment.component.ts.

7.2 Class Naming

When naming your classes, use the upper camel case style with the added suffix representing your file type – TcHomeComponent, AuthService.

7.3 Folder Structure

|-- app
	|-- modules
		|-- home
			|-- [+] components
			|-- [+] pages
			|-- home-routing.module.ts
			|-- home.module.ts
	|-- core
		|-- [+] authentication
		|-- [+] footer
		|-- [+] guards
		|-- [+] http
		|-- [+] interceptors
		|-- [+] mocks
		|-- [+] services
		|-- [+] header
		|-- core.module.ts
		|-- ensureModuleLoadedOnceGuard.ts
		|-- logger.service.ts
	|
	|-- shared
		|-- [+] components
		|-- [+] directives
		|-- [+] pipes
		|-- [+] models
	|
	|-- [+] configs
|-- assets
	|-- scss
		|-- [+] partials
		|-- _base.scss
		|-- styles.scss

One of the most important things to know about Angular is that it utilizes Angular Modules to tightly group related features. Using Angular modules is an Angular folder structure best practice. Each module should have its folder, and it should be namedaccording to its Module Name.Angular does not distinguish between the different Modules, but we should classify our modules for better understanding.

The most important Angular Modules are –

7.3.1 Root Module

Root module is needed for starting an Angular app. This module loads all the root components and other modules. Root Modules are alternatively known as AppModule and are created under the/src/app folder.

7.3.2 Feature Module

Feature module, as the name suggests, implements a specific feature of your Angular app. All the associated pipes, components, and directives that help implement the feature become a part of its module. You can create sub-folders for your directives and pipes under the module folder. Make a components folder to place all the components in one organized place.  Having a feature module is an organizational best practice as opposed to the core concept of Angular API.

7.3.3 Shared Module

Next on the list in shared modules. Creating shared modules in your Angular project helps you to organize and streamline your code. You can gather all the commonly used components, pipes, and directives into one module and then import the entire module whenever needed in any part of your application.

7.3.4 Core Module

And last but not least, we have the core modules. Core module is a module created to define the common services of your Angular app. The services defined under a Core Module are defined as an instance once. This module is imported from the main module as it has singleton services that any element of your Angular app can use. You should import the core module from the root module only.

8. Build Reusable Components

Building reusable components is a golden rule that cannot be omitted when discussing Angular.js best practices. If there is a part of your Angular app’s UI that you know you would need in multiple places, build a component for it and use the component. This will help in implementing the UI element consistently throughout the application. And also, if your app goes through a redesign process for some reason, you will not have to change the UI code at 100s of places. You need to change the component, and you’re good to go.

9. Use Index.ts

Index.tsallows Angular developers to keep all related things closely packed together, so they don’t need to bother about the source file name. This helps to reduce the size of introductory statements.

For example, we have /heroes/index.ts as

//heroes/index.ts

export * from './hero.model';
export * from './hero.service';
export { HeroComponent } from './hero.component';

We can import everything by using source folder name –

import { Hero, HeroService } from '../heroes'; // index is implied

10. Avoid using Logic in the Component

Many developers mix the components and business logic, resulting in a complex and untidy mess that is difficult to comprehend. Hence, it is important to follow Angular 2 development best practice guidelines and keep the logic separate from your components.

Advantages of keeping Logic and Components separate

• The testing process of UI and components differ from Logic Testing.
• Different services for Business Logic are used to improve code reusability and quality. Having logic in a separate service will allow you to use it in multiple components. This would result in a reduction of build size and also lesser code.

11. Prevent Memory Leaks

A memory leak is the gradual loss of available computer space when an application incorrectly manages memory allocations where the obsolete memory isn’t properly released. Another way memory leak can happen is when the running code can no longer access an object stored in the memory.  Here are some important suggestions and best practices for securing your Angular app against memory leaks –

11.1 Use of async pipe

You can either utilize observables or use async pipe and promise to prevent memory leaks. It is advisable to prevent subscribing observables in the component and binding it in view.  Hence, the observable technique needs to be entirely done to reduce the chances of a memory leak.

11.2 Using ‘take(1)’

take(1) is an operator that takes the value and allows it is not subscribing whenever a new value gets diagnosed. It will ensure that you receive data only once, hence preventing data leaks efficiently.

data$.pipe(take(1)).subscribe(res=>console.log(res))

11.3 Using ‘takeUntill.’

takeUntill is another operator that is to be used when you want to monitor the two observables and dispose of the subscription after the observables emit the value or get completed. It helps you remain confident about your observables not getting leaked till they deliver their value.

Now, using a command such as “ngUnsubscribe.next()” and “this.ngUnsubscribe.complete()” in the ‘ngOnDestroy()‘ field so that it will prevent the emission from taking place as soon as the component destroyed.

Here’s how it happens;

export class SimpleComponent implements OnInit, OnDestroy {
  constructor(private route: ActivatedRoute,
              private http: Http) {
  }
  ngOnInit() {
    this.route.params
      .takeUntil(componentDestroyed(this))
      .subscribe(params => {
        // do something
      });
    this.http.get("/load")
      .takeUntil(componentDestroyed(this))
      .subscribe(result => {
        // do something
      });
  }
  ngOnDestroy() {
    // empty
  }
}

12. Always Document

And last but certainly not least, you should always pay attention to documentation. Write comments alongside the codes to help other developers involved in the project to understand the intent, purpose, and logic of your code. It helps to manage the code and adds to the readability of the code. Also, document each method and variable’s use and role.

Wrapping up!

Following these best practices in Angular will help your Angular project reach new heights in lesser time and also help you reduce unnecessary money and resources spent on the overall Angular project. Ensure to follow these Angular best practices in 2024 to get ahead of your competitors and provide your customers with the best Angular experience when they browse your web apps.