How to use Services in Angular ?

In this tutorial , we are going to see how to create and use services in angular and the purpose of using them in our application.

What is a Service in Angular ?

In Angular , a service is a class that provides a specific service or functionality, such as logging, data access, or message handling, that can be shared across multiple components in an Angular application.

Services are typically injected into components using Angular’s dependency injection system, allowing the service to be used in the component.

Angular services are typically used for tasks that are not specific to a particular component, such as data access or application-wide messaging.

By creating a service, you can separate the logic for these tasks from the components in your application, making your code cleaner and easier to maintain.

Services are typically created using the @Injectable decorator from the @angular/core module, which specifies that the class can be used with Angular’s dependency injection system.

How to create services in Angular using CLI ?

To create an Angular service, you will need to have the Angular CLI installed on your computer then , you need to use the following steps :

				
					ng generate service <service-name>

This command will create a new Angular service with the given name in the current directory.

The service will be created in a new subfolder with the same name as the service, and the service file itself will be named .service.ts.

If you want to create the service in a different directory, you can specify the path to the directory where you want to create the service using the --directory or -d flag like this :

				
					ng generate service <service-name> --directory <path/to/directory>

This will create the service in the specified directory, rather than the current directory.

It’s also worth mentioning that the ng generate service command is a shorthand for the ng g service command, so you can use either one to create a new Angular service using the Angular CLI.

How to use Services in Angular ?

Here is an example of a simple Angular service that provides a greeting message.

This example will show you how to use services in angular :

				
					import { Injectable } from '@angular/core';

@Injectable({
  providedIn: 'root'
})
export class GreetingService {
  constructor() {}

  public getGreeting(): string {
    return 'Hello, XperTuto.com !';
  }
}

This service has a single method, getGreeting(), which returns the greeting message "Hello, XperTuto.com".

The service is marked with the @Injectable decorator, which tells Angular that this service can be injected into other components and services as a dependency.

To use this service in another component, you need first to inject it into the component’s constructor, like this :

				
					import { Component } from '@angular/core';
import { GreetingService } from './greeting.service';

@Component({
  selector: 'app-greeting',
  templateUrl: './greeting.component.html',
  styleUrls: ['./greeting.component.css']
})
export class GreetingComponent {
  constructor(private greetingService: GreetingService) {}

  public getGreeting(): string {
    return this.greetingService.getGreeting();
  }
}

In this example, the GreetingComponent injects the GreetingService into its constructor and uses it to get the greeting message.

The component then provides a public method, getGreeting(), which delegates to the getGreeting() method of the GreetingService to return the greeting message.

This is just a simple example to illustrate how you can create and use an Angular service.

In a real-world application, your service might provide more complex functionality, such as making HTTP requests to a server or performing data manipulation.

Advantages of using Angular Services

There are several advantages to using Angular services in your application:

Services in angular allow you to abstract common functionality into a single, reusable unit. This means you can write the code for a particular feature or behavior once, and then use that service in multiple places throughout your application.
Services can be easily shared and injected into multiple components, directives, and other services. This allows you to create highly modular and reusable code, and it can make it easier to test and debug your application.
Services are a good way to implement separation of business logic in your application. By dividing your application into different services, each with a specific responsibility, you can make your code more organized and easier to understand.
Services can help you manage state in your application. For example, you can use a service to store data that needs to be accessed by multiple components, or to share data between components that don’t have a direct parent-child relationship.
Services in angular are a powerful tool for decoupling different parts of your application. This can make your code more flexible and adaptable.

Overall, Angular services are an important part of the Angular framework, and they provide many benefits that can help you build more scalable, maintainable, and modular applications.

References and Links

Here are more related references and links that discuss the same subject:

Angular Front-End web development

How to use Services in Angular ?

Table of Contents

What is a Service in Angular ?

How to create services in Angular using CLI ?

How to use Services in Angular ?

Advantages of using Angular Services

References and Links

How to use ngOnDestroy lifecycle hook in Angular ?

How to use Dependency Injection in Angular ?

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