Features of Providedln

What is dependency injection?

Dependency Injection is a design pattern that helps in the creation and management of object dependencies. In Angular, components and services often have dependencies on other components or services, and dependency injection allows these dependencies to be provided to the dependent objects at runtime. This helps in modularity, reusability, and testability in Angular applications....

What is Providedln?

The providedIn property is used to specify the root injector or module where a service or module should be provided. It essentially tells Angular where the dependency should be available and how it should be instantiated. This property is typically used in the @Injectable() decorator for services or in the module metadata for modules....

Features of Providedln

Scoping and Visibility: By controlling the scope of services, you can ensure that they are only available where they are needed that helps in better code organization and maintainability.Singleton vs. Multiple Instances: Depending on your application’s requirements, you can choose to have a single instance of a service shared across the entire application or multiple instances for different modules or components.Lazy Loading: When using the Angular module system with lazy loading, specifying the providedIn property correctly can help optimize your application’s performance by ensuring that services are only loaded when needed....

Example of ProvidedIn in Angular

To illustrate the usage of providedIn, let’s create a simple Angular application with a service and two components:...

Folder Structure:

Folder Structure...

Conclusion

Both components are able to access the same instance of the DataService class because it was provided at the root level....