ASP.NET Core uses a built-in dependency injection mechanism provided by Microsoft. This blog post introduces how to use the same mechanism in .NET Core console applications. For those who like other DI/IoC frameworks, this article provides a demo about how to use Autofac with .NET Core framework-level dependency injection.
Framework-Level Dependency Injection in ASP.NET Core
I don't describe here details of dependency injection in ASP.NET Core. Those who want to find out more about it can skim through these writings: