Microsoft.Extensions.DependencyInjection

Microsoft.Extensions.DependencyInjection is a lightweight, built-in dependency injection (DI) container library for .NET applications. It provides a simple and flexible way to manage object dependencies and promote loose coupling, primarily used in ASP.NET Core and other .NET projects. The library supports constructor injection, service lifetimes (transient, scoped, singleton), and service registration through an IServiceCollection interface.

Also known as: DependencyInjection, Microsoft DI, MS DI, IServiceCollection, ServiceCollection

Why learn Microsoft.Extensions.DependencyInjection?

Developers should learn and use this library when building .NET applications, especially ASP.NET Core web apps, to implement dependency injection patterns that improve testability, maintainability, and scalability. It is essential for managing service dependencies in modern .NET architectures, such as in microservices or MVC applications, where decoupling components is critical for unit testing and code reuse.

Learning Resources

• docs: Microsoft Docs: Dependency injection in .NET
• course: Pluralsight Course: Dependency Injection in ASP.NET Core
• video: YouTube: Dependency Injection in ASP.NET Core Explained
• book: Book: Dependency Injection Principles, Practices, and Patterns