Dependency injection is a technique of implementing inversion of management (IoC), which is a design precept that states that an abstraction layer needs to be used to deal with software dependencies. In different phrases, as a substitute of sophistication A referencing class B, class A ought to reference an abstraction (i.e., an interface) that class B implements. So, as a substitute of sophistication A relying on class B, class B will rely upon an interface that class A controls. That is the inversion of management.
The usage of interfaces permits builders to simply swap in several implementations of these interfaces. Thus inversion of management and dependency injection allow you to construct functions which can be loosely coupled, modular, testable, and maintainable. Observe there are a lot of methods to implement dependency injection in ASP.NET Core. Whereas various IoC containers akin to StructureMap and Ninject present extra superior options, ASP.NET Core’s built-in DI container is quick and simple to make use of.
Constructor injection vs. the IServiceProvider interface
Each constructor injection and the IServiceProvider interface are strategies for resolving dependencies. Nonetheless, they differ considerably in implications and use circumstances. With constructor injection, the dependencies of a category are handed by the category constructor at compile time. With the IServiceProvider interface, the dependencies are retrieved at run time. Thus, IServiceProvider offers an possibility when the dependencies are unknown throughout compilation or could change after compilation.
