Angular

How to Create Standalone Components in Angular

Published May 12, 2023

Updated Nov 22, 2023

4 min read

This article was written over 18 months ago and may contain information that is out of date. Some content may be relevant but please refer to the relevant official documentation or available resources for the latest information.

Angular has become one of the most popular frameworks to build web applications today.

One of the key features of the framework is its component-based architecture, which allows best practices like modularity and reusability. Each Angular component consists of a template, a TypeScript class and metadata.

In this blog post, we will dive deeper into standalone components, and we will explore the anatomy of an application based on them.

For the demo application, we will create a card-like component which can be used to render blog posts in a web application.

Prerequisites

You'll need to have installed the following tools in your local environment:

The latest LTS version of Node.js is recommended.
Either NPM or Yarn as a package manager.
The Angular CLI tool(Command-line interface for Angular).

Initialize the Project

Let's create a project from scratch using the Angular CLI tool:

ng new demo-angular-standalone-components --routing --prefix corp --style css --skip-tests

This command will initialize a base project using some configuration options:

--routing. It will create a routing module.
--prefix corp. It defines a prefix to be applied to the selectors for created components(corp in this case). The default value is app.
--style css. The file extension for the styling files.
--skip-tests. Disable the generation of testing files for the new project.

If you pay attention to the generated files and directories, you'll see an initial project structure including the main application module and component:

|- src/
    |- app/
        |- app.module.ts
        |- app-routing.module.ts
        |- app.component.ts

Creating Standalone Components

First, let's create the custom button to be used as part of the Card component later. Run the following command on your terminal:

ng generate component button --inline-template --standalone

It will create the files for the component. The --standalone option will generate the component as standalone.

Let's update the button.component.ts file using the content below.

import { Component } from '@angular/core';
import { CommonModule } from '@angular/common';

@Component({
  selector: 'corp-button',
  standalone: true,
  imports: [CommonModule],
  template: `
    <button class="corp-button">
      <ng-content></ng-content>
    </button>
  `,
  styleUrls: ['./button.component.css']
})
export class ButtonComponent {

}

Pay attention to this component since it's marked as standalone: true.

Starting with Angular v15: components, directives, and pipes can be marked as standalone by using the flag standalone.

When a class is marked as standalone, it does not need to be declared as part of an NgModule. Otherwise, the Angular compiler will report an error.

Also, imports can be used to reference the dependencies.

The imports property specifies the standalone component's template dependencies — those directives, components, and pipes that can be used within its template. Standalone components can import other standalone components, directives, and pipes as well as existing NgModules.

Next, let's create the following components: card-title, card-content, card-actions and card.

This can be done at once using the next commands.

ng generate component card-title --inline-template --standalone
ng generate component card-content --inline-template --standalone
ng generate component card-actions --inline-template --standalone
ng generate component card --inline-template --standalone

On card-title.component.ts file, update the content as follows:

//card-title.component.ts

import { Component } from '@angular/core';
import { CommonModule } from '@angular/common';

@Component({
  selector: 'corp-card-title',
  standalone: true,
  imports: [CommonModule],
  template: `
    <h4>
        <ng-content></ng-content>
    </h4>
  `,
  styleUrls: ['./card-title.component.css']
})
export class CardTitleComponent {

}

Next, update the card-content.component.ts file:

//card-content.component.ts

import { Component } from '@angular/core';
import { CommonModule } from '@angular/common';

@Component({
  selector: 'corp-card-content',
  standalone: true,
  imports: [CommonModule],
  template: `
    <p class="corp-card-content">
      <ng-content></ng-content>
    </p>
  `,
  styleUrls: ['./card-content.component.css']
})
export class CardContentComponent {

}

The card-actions.component.ts file should have the content below:

// card-actions.component.ts

import { Component } from '@angular/core';
import { CommonModule } from '@angular/common';

@Component({
  selector: 'corp-card-actions',
  standalone: true,
  imports: [CommonModule],
  template: `
    <div class="corp-card-actions">
      <ng-content></ng-content>
    </div>
  `,
  styleUrls: ['./card-actions.component.css']
})
export class CardActionsComponent {

}

Finally, the card.component.ts file should be defined as follows:

//card.component.ts

import { Component } from '@angular/core';
import { CommonModule } from '@angular/common';

@Component({
  selector: 'corp-card',
  standalone: true,
  imports: [CommonModule],
  template: `
    <div class="corp-card">
        <ng-content></ng-content>
    </div>
  `,
  styleUrls: ['./card.component.css']
})
export class CardComponent {

}

Using Standalone Components

Once all Standalone components are created, we can use them without the need to define an NgModule.

Let's update the app.component.ts file as follows:


// app.component.ts

import { Component } from '@angular/core';
import { ButtonComponent } from './button/button.component';
import { CardComponent } from './card/card.component';
import { CardTitleComponent } from './card-title/card-title.component';
import { CardContentComponent } from './card-content/card-content.component';
import { CardActionsComponent } from './card-actions/card-actions.component';

@Component({
  selector: 'corp-root',
  standalone: true,
  imports: [
    ButtonComponent,
    CardComponent,
    CardTitleComponent,
    CardContentComponent,
    CardActionsComponent
  ],
  templateUrl: './app.component.html',
  styleUrls: ['./app.component.css']
})
export class AppComponent {
  title = 'demo-angular-standalone-components';
}

Again, this Angular component is set as standalone: true and the imports section specifies the other components created as dependencies. Then, we can update the app.component.html file and use all the standalone components.

<!-- app.component.html -->

<h2>Latest Posts</h2>

<corp-card>
  <corp-card-title>Introduction to Angular</corp-card-title>
  <corp-card-content>
    Angular is a component-based framework for building scalable web applications.
  </corp-card-content>
  <corp-card-actions>
    <corp-button>View</corp-button>
  </corp-card-actions>
</corp-card>

<corp-card>
  <corp-card-title>Introduction to TypeScript</corp-card-title>
  <corp-card-content>
    TypeScript is a strongly typed programming language that builds on JavaScript, providing better tooling at any scale.
  </corp-card-content>
  <corp-card-actions>
    <corp-button>View</corp-button>
  </corp-card-actions>
</corp-card>

This may not work yet, since we need to configure the Angular application and get rid of the autogenerated module defined under the app.module.ts file.

Bootstrapping the Application

Angular provides a new API to use a standalone component as the application's root component.

Let's update the main.ts file with the following content:

// main.ts
import { bootstrapApplication } from '@angular/platform-browser';
import { AppComponent } from './app/app.component';

bootstrapApplication(AppComponent);

As you can see, we have removed the previous bootstrapModule call and the bootstrapApplication function will render the standalone component as the application's root component. You can find more information about it here.

Live Demo and Source Code

Want to play around with this code? Just open the Stackblitz editor or the preview mode in fullscreen.

Conclusion

We’re now ready to use and configure the Angular components as standalone and provide a simplified way to build Angular applications from scratch. Do not forget that you can mark directives and pipes as standalone: true. If you love Angular as much as we do, you can start building today using one of our starter.dev kits or by looking at their related showcases for more examples.

This Dot is a consultancy dedicated to guiding companies through their modernization and digital transformation journeys. Specializing in replatforming, modernizing, and launching new initiatives, we stand out by taking true ownership of your engineering projects.

We love helping teams with projects that have missed their deadlines or helping keep your strategic digital initiatives on course. Check out our case studies and our clients that trust us with their engineering.

About the author(s)

Luis Aviles
Luis is a Senior Software Engineer and Google Developer Expert in Web Technologies and Angular. He is an author of online courses, technical articles, and a public speaker. He has participated in different international technology conferences, giving technical talks, workshops, and training sessions. He’s passionate about the developer community and he loves to help junior developers and professionals to improve their skills. When he’s not coding, Luis is doing photography or Astrophotography.
@luixaviles @luixaviles

Overview of the New Signal APIs in Angular

Overview of the New Signal APIs in Angular Google's Minko Gechev and Jeremy Elbourn announced many exciting things at NG Conf 2024. Among them is the addition of several new signal-based APIs. They are already in developer preview, so we can play around with them. Let's dig into it, starting with signal-based inputs and the new matching outputs API. Signal Based Inputs Discussions about signal-based inputs have been taking place in the Angular community for some time now, and they are finally here. Until now, you used the @Input() decorator to define inputs. This is what you'd have to write in your component to declare an optional and a required input: ` With the new signal-based inputs, you can write much less boilerplate code. Here is how you can define the same inputs using the new syntax: ` It's not only less boilerplate, but because the values are signals, you can also use them directly in computed signals and effects. That, effectively, means you get to avoid computing combined values in ngOnChanges or using setters for your inputs to be able to compute derived values. In addition, input signals are read-only. The New Output I intentionally avoid calling them signal-based outputs because they are not. They still work the same way as the old outputs. The Angular team has just introduced a new output API that is more consistent with the latest inputs API and allows you to write less boilerplate, similar to the new input API. Here is how you would define an output until now: ` Here is how you can define the same output using the new syntax: ` The thing I like about the new output API is that sometimes it happens to me that I forget to instantiate the EventEmitter because I do this instead: ` You won't forget to instantiate the output with the new syntax because the output function does it for you. Signal Queries I am sure most readers know the @ViewChild, @ViewChildren, @ContentChild, and @ContentChildren decorators very well and have experienced the pain of triggering the infamous ExpressionChangedAfterItHasBeenCheckedError or having the values unavailable when needed. Here is a refresher on how you would use these decorators until now: ` With the new signal queries, similar to the new input API, the values are signals, and you can use them directly in computed signals and effects. You can define the same queries using the new syntax: ` Jeremy Elbourn mentioned that the new signal queries have better type inference and are more consistent with the new input and output APIs. He also showcased a brand new feature not available with the old queries. You can now define a query as required, and the Angular compiler will throw an error if the query has no result, guaranteeing that the value won't be undefined. Here is how you can define a required query: ` Model Inputs Jeremy and Minko announced the last new feature is the model inputs. The name is vague, but the feature is cool—it simplifies the definition of two-way bindings. Until now, to achieve two-way binding, you would have to define an input and an output following a given naming convention. @Input and @Output had to be defined with the same name (followed by "Change" in the case of the output). Then, you could use the template's [()] syntax. ` ` That way, you could keep the value in sync between the parent and the child component. With the new model inputs, you can define a two-way binding with a single line of code. Here is how you can define the same two-way binding using the new syntax: ` The html template stays the same: ` The model function returns a writable signal that can be updated directly. The value will be propagated back to any two-way bindings. Conclusion The new signal-based APIs are a great addition to Angular. They allow you to write less boilerplate code and make your components more reactive. The new APIs are already in developer preview, so you can start playing around with them today. I look forward to seeing how the community will adopt these new features and what other exciting things the Angular team has in store for us, such as zoneless apps by default....

Apr 3, 2024

3 mins

AngularJavaScript

Exploring Angular Forms: A New Alternative with Signals

Exploring Angular Forms: A New Alternative with Signals In the world of Angular, forms are essential for user interaction, whether you're crafting a simple login page or a more complex user profile interface. Angular traditionally offers two primary approaches: template-driven forms and reactive forms. In my previous series on Angular Reactive Forms, I explored how to harness reactive forms' power to manage complex logic, create dynamic forms, and build custom form controls. A new tool for managing reactivity - signals - has been introduced in version 16 of Angular and has been the focus of Angular maintainers ever since, becoming stable with version 17. Signals allow you to handle state changes declaratively, offering an exciting alternative that combines the simplicity of template-driven forms with the robust reactivity of reactive forms. This article will examine how signals can add reactivity to both simple and complex forms in Angular. Recap: Angular Forms Approaches Before diving into the topic of enhancing template-driven forms with signals, let’s quickly recap Angular's traditional forms approaches: 1. Template-Driven Forms: Defined directly in the HTML template using directives like ngModel, these forms are easy to set up and are ideal for simple forms. However, they may not provide the fine-grained control required for more complex scenarios. Here's a minimal example of a template-driven form: ` ` 2. Reactive Forms: Managed programmatically in the component class using Angular's FormGroup, FormControl, and FormArray classes; reactive forms offer granular control over form state and validation. This approach is well-suited for complex forms, as my previous articles on Angular Reactive Forms discussed. And here's a minimal example of a reactive form: ` ` Introducing Signals as a New Way to Handle Form Reactivity With the release of Angular 16, signals have emerged as a new way to manage reactivity. Signals provide a declarative approach to state management, making your code more predictable and easier to understand. When applied to forms, signals can enhance the simplicity of template-driven forms while offering the reactivity and control typically associated with reactive forms. Let’s explore how signals can be used in both simple and complex form scenarios. Example 1: A Simple Template-Driven Form with Signals Consider a basic login form. Typically, this would be implemented using template-driven forms like this: ` ` This approach works well for simple forms, but by introducing signals, we can keep the simplicity while adding reactive capabilities: ` ` In this example, the form fields are defined as signals, allowing for reactive updates whenever the form state changes. The formValue signal provides a computed value that reflects the current state of the form. This approach offers a more declarative way to manage form state and reactivity, combining the simplicity of template-driven forms with the power of signals. You may be tempted to define the form directly as an object inside a signal. While such an approach may seem more concise, typing into the individual fields does not dispatch reactivity updates, which is usually a deal breaker. Here’s an example StackBlitz with a component suffering from such an issue: Therefore, if you'd like to react to changes in the form fields, it's better to define each field as a separate signal. By defining each form field as a separate signal, you ensure that changes to individual fields trigger reactivity updates correctly. Example 2: A Complex Form with Signals You may see little benefit in using signals for simple forms like the login form above, but they truly shine when handling more complex forms. Let's explore a more intricate scenario - a user profile form that includes fields like firstName, lastName, email, phoneNumbers, and address. The phoneNumbers field is dynamic, allowing users to add or remove phone numbers as needed. Here's how this form might be defined using signals: ` > Notice that the phoneNumbers field is defined as a signal of an array of signals. This structure allows us to track changes to individual phone numbers and update the form state reactively. The addPhoneNumber and removePhoneNumber methods update the phoneNumbers signal array, triggering reactivity updates in the form. ` > In the template, we use the phoneNumbers signal array to dynamically render the phone number input fields. The addPhoneNumber and removePhoneNumber methods allow users to reactively add or remove phone numbers, updating the form state. Notice the usage of the track function, which is necessary to ensure that the ngFor directive tracks changes to the phoneNumbers array correctly. Here's a StackBlitz demo of the complex form example for you to play around with: Validating Forms with Signals Validation is critical to any form, ensuring that user input meets the required criteria before submission. With signals, validation can be handled in a reactive and declarative manner. In the complex form example above, we've implemented a computed signal called formValid, which checks whether all fields meet specific validation criteria. The validation logic can easily be customized to accommodate different rules, such as checking for valid email formats or ensuring that all required fields are filled out. Using signals for validation allows you to create more maintainable and testable code, as the validation rules are clearly defined and react automatically to changes in form fields. It can even be abstracted into a separate utility to make it reusable across different forms. In the complex form example, the formValid signal ensures that all required fields are filled and validates the email and phone numbers format. This approach to validation is a bit simple and needs to be better connected to the actual form fields. While it will work for many use cases, in some cases, you might want to wait until explicit "signal forms" support is added to Angular. Tim Deschryver started implementing some abstractions around signal forms, including validation and wrote an article about it. Let's see if something like this will be added to Angular in the future. Why Use Signals in Angular Forms? The adoption of signals in Angular provides a powerful new way to manage form state and reactivity. Signals offer a flexible, declarative approach that can simplify complex form handling by combining the strengths of template-driven forms and reactive forms. Here are some key benefits of using signals in Angular forms: 1. Declarative State Management: Signals allow you to define form fields and computed values declaratively, making your code more predictable and easier to understand. 2. Reactivity: Signals provide reactive updates to form fields, ensuring that changes to the form state trigger reactivity updates automatically. 3. Granular Control: Signals allow you to define form fields at a granular level, enabling fine-grained control over form state and validation. 4. Dynamic Forms: Signals can be used to create dynamic forms with fields that can be added or removed dynamically, providing a flexible way to handle complex form scenarios. 5. Simplicity: Signals can offer a simpler, more concise way to manage form states than traditional reactive forms, making building and maintaining complex forms easier. Conclusion In my previous articles, we explored the powerful features of Angular reactive forms, from dynamic form construction to custom form controls. With the introduction of signals, Angular developers have a new tool that merges the simplicity of template-driven forms with the reactivity of reactive forms. While many use cases warrant Reactive Forms, signals provide a fresh, powerful alternative for managing form state in Angular applications requiring a more straightforward, declarative approach. As Angular continues to evolve, experimenting with these new features will help you build more maintainable, performant applications. Happy coding!...

Oct 4, 2024

5 mins

AngularJavaScript

How to Manage Breakpoints using BreakpointObserver in Angular

Defining Breakpoints is important when you start working with Responsive Design and most of the time they're created using CSS code. For example: ` By default, the text size value will be 12px, and this value will be changed to 14px when the viewport gets changed to a smaller screen (a maximum width of 600px). That solution works. However, what about if you need to _listen_ for certain breakpoints to perform changes in your application? This may be needed to configure third-party components, processing events, or any other. Luckily, Angular comes with a handy solution for these scenarios: the BreakpointObserver. Which is a utility for checking the matching state of @media queries. In this post, we will build a sample application to add the ability to configure certain breakpoints, and being able to _listen_ to them. Project Setup Prerequisites You'll need to have installed the following tools in your local environment: - Node.js. Preferably the latest LTS version. - A package manager. You can use either NPM or Yarn. This tutorial will use NPM. Creating the Angular Project Let's start creating a project from scratch using the Angular CLI tool. ` This command will initialize a base project using some configuration options: - --routing. It will create a routing module. - --prefix corp. It defines a prefix to be applied to the selectors for created components(corp in this case). The default value is app. - --style scss. The file extension for the styling files. - --skip-tests. it avoids the generations of the .spec.ts files, which are used for testing Adding Angular Material and Angular CDK Before creating the breakpoints, let's add the Angular Material components, which will install the Angular CDK library under the hood. ` Creating the Home Component We can create a brand new component to handle a couple of views to be updated while the breakpoints are changing. We can do that using the ng generate command. ` Pay attention to the output of the previous command since it will show you the auto-generated files. Update the Routing Configuration Remember we used the flag --routing while creating the project? That parameter has created the main routing configuration file for the application: app-routing.module.ts. Let's update it to be able to render the home component by default. ` Update the App Component template Remove all code except the router-outlet placeholder: ` This will allow rendering the home component by default once the routing configuration is running. Using the BreakpointObserver The application has the Angular CDK installed already, which has a layout package with some utilities to build responsive UIs that _react_ to screen-size changes. Let's update the HomeComponent, and inject the BreakpointObserver as follows. ` Once the BreakpointObserver is injected, we'll be able to evaluate media queries to determine the current screen size, and perform changes accordingly. Then, a breakpoint$ variable references an _observable_ object after a call to the observe method. The observe method gets an observable of results for the given queries, and can be used along with predetermined values defined on Breakpoints as a constant. Also, it's possible to use custom breakpoints such as (min-width: 500px). Please refer to the documentation to find more details about this. Next, you may need to _subscribe_ to the breakpoint$ observable to see the emitted values after matching the given queries. Again, let's update the home.component.ts file to do that. ` In the above code, the ngOnInit method is used to perform a _subscription_ to the breakpoint$ observable and the method breakpointChanged will be invoked every time a breakpoint match occurs. As you may note, the breakpointChanged method verifies what Breakpoint value has a match through isMatched method. In that way, the current component can perform changes after a match happened (in this case, it just updates the value for the currentBreakpoint attribute). Using Breakpoint values on the Template Now, we can set a custom template in the home.component.html file and be able to render a square according to the currentBreakpoint value. ` The previous template will render the current media query value at the top along with a rectangle according to the size: Large, Medium, Small or Custom. Live Demo and Source Code Want to play around with this code? Just open the Stackblitz editor or the preview mode in fullscreen. Find the complete angular project in this GitHub repository: breakpointobserver-example-angular. Do not forget to give it a star ⭐️ and play around with the code. Feel free to reach out on Twitter if you have any questions. Follow me on GitHub to see more about my work....

Apr 14, 2022

4 mins

AngularTypeScriptWeb Development

“Music and code have a lot in common,” freeCodeCamp’s Jessica Wilkins on what the tech community is doing right to onboard new software engineers

Before she was a software developer at freeCodeCamp, Jessica Wilkins was a classically trained clarinetist performing across the country. Her days were filled with rehearsals, concerts, and teaching, and she hadn’t considered a tech career until the world changed in 2020. > “When the pandemic hit, most of my gigs were canceled,” she says. “I suddenly had time on my hands and an idea for a site I wanted to build.” That site, a tribute to Black musicians in classical and jazz music, turned into much more than a personal project. It opened the door to a whole new career where her creative instincts and curiosity could thrive just as much as they had in music. Now at freeCodeCamp, Jessica maintains and develops the very JavaScript curriculum that has helped her and millions of developers around the world. We spoke with Jessica about her advice for JavaScript learners, why musicians make great developers, and how inclusive communities are helping more women thrive in tech. Jessica’s Top 3 JavaScript Skill Picks for 2025 If you ask Jessica what it takes to succeed as a JavaScript developer in 2025, she won’t point you straight to the newest library or trend. Instead, she lists three skills that sound simple, but take real time to build: > “Learning how to ask questions and research when you get stuck. Learning how to read error messages. And having a strong foundation in the fundamentals” She says those skills don’t come from shortcuts or shiny tools. They come from building. > “Start with small projects and keep building,” she says. “Books like You Don’t Know JS help you understand the theory, but experience comes from writing and shipping code. You learn a lot by doing.” And don’t forget the people around you. > “Meetups and conferences are amazing,” she adds. “You’ll pick up things faster, get feedback, and make friends who are learning alongside you.” Why So Many Musicians End Up in Tech A musical past like Jessica’s isn’t unheard of in the JavaScript industry. In fact, she’s noticed a surprising number of musicians making the leap into software. > “I think it’s because music and code have a lot in common,” she says. “They both require creativity, pattern recognition, problem-solving… and you can really get into flow when you’re deep in either one.” That crossover between artistry and logic feels like home to people who’ve lived in both worlds. What the Tech Community Is Getting Right Jessica has seen both the challenges and the wins when it comes to supporting women in tech. > “There’s still a lot of toxicity in some corners,” she says. “But the communities that are doing it right—like Women Who Code, Women in Tech, and Virtual Coffee—create safe, supportive spaces to grow and share experiences.” She believes those spaces aren’t just helpful, but they’re essential. > “Having a network makes a huge difference, especially early in your career.” What’s Next for Jessica Wilkins? With a catalog of published articles, open-source projects under her belt, and a growing audience of devs following her journey, Jessica is just getting started. She’s still writing. Still mentoring. Still building. And still proving that creativity doesn’t stop at the orchestra pit—it just finds a new stage. Follow Jessica Wilkins on X and Linkedin to keep up with her work in tech, her musical roots, and whatever she’s building next. Sticker illustration by Jacob Ashley....

Apr 25, 2025

3 mins

JavaScriptSoftware Engineering

Let's innovate together!

We're ready to be your trusted technical partners in your digital innovation journey.

Whether it's modernization or custom software solutions, our team of experts can guide you through best practices and how to build scalable, performant software that lasts.

How to Create Standalone Components in Angular

Prerequisites

Initialize the Project

Creating Standalone Components

Using Standalone Components

Bootstrapping the Application

Live Demo and Source Code

Conclusion

Luis Aviles

You might also like

Overview of the New Signal APIs in Angular

Exploring Angular Forms: A New Alternative with Signals

How to Manage Breakpoints using BreakpointObserver in Angular

“Music and code have a lot in common,” freeCodeCamp’s Jessica Wilkins on what the tech community is doing right to onboard new software engineers

Let's innovate together!

You might also like

Overview of the New Signal APIs in Angular

Exploring Angular Forms: A New Alternative with Signals

How to Manage Breakpoints using BreakpointObserver in Angular

“Music and code have a lot in common,” freeCodeCamp’s Jessica Wilkins on what the tech community is doing right to onboard new software engineers