Függséginjektálás

Függséginjektálás, also known as dependency injection, is a design pattern used in software development to implement inversion of control (IoC) between classes and their dependencies. It is a technique where an object receives other objects it depends on, rather than creating them itself. This approach promotes loose coupling and makes code more modular, testable, and maintainable.

In dependency injection, the dependencies of a class are provided from the outside, typically through the class constructor, although they can also be provided through methods or properties. This allows for greater flexibility and reusability of code, as the same class can work with different implementations of its dependencies. It also simplifies testing, as dependencies can be easily mocked or stubbed.

There are several types of dependency injection, including constructor injection, setter injection, and interface injection. Constructor injection is the most common and involves passing dependencies through the class constructor. Setter injection involves providing dependencies through setter methods, while interface injection involves defining an interface that the class implements to receive its dependencies.

Dependency injection is widely used in modern software development and is a key concept in many frameworks and libraries, such as Spring, Angular, and .NET Core. It is particularly useful in large-scale applications where managing dependencies can become complex. By using dependency injection, developers can create more robust and scalable applications that are easier to maintain and extend.