Perfect console application in .net Core: set up dependency injection

It may seem that when creating a console application we are doomed to use statics all over the code. Well.. we’re not! I’ll show you how to set up dependency injection and use it.

This is a part of a series of articles about writing a perfect console application in .net core 2. Feel free to read more:

Dependency Injection

There are many packages that can provide dependency injection, but I chose SimpleInjector, because I know it well. It’s also quite fast, according to Daniel Palme’s article. Here is how whole calss looks like:

    using System.Linq;

    using SimpleInjector;

    public static class ContainerConfig
        private static Container Container;

        public static void Init()
            Container = new Container();



        public static TService GetInstance<TService>() where TService : class
            return Container.GetInstance<TService>();

        private static void RegisterAllTypesWithConvention()
            var typesWithInterfaces = typeof(Program).Assembly.GetExportedTypes()
                .Where(t => t.Namespace.StartsWith(""))
                .Where(ts => ts.GetInterfaces().Any() && ts.IsClass).ToList();
            var registrations = typesWithInterfaces.Select(ti => new
                    Service = ti.GetInterfaces().Single(), Implementation = ti

            foreach (var reg in registrations)
                Container.Register(reg.Service, reg.Implementation, Lifestyle.Singleton);

Notice RegisterAllTypesWithConvention method – it is the way to register all interface implementations, that follows a simple naming convention. When interface will have an additional I in the name comparing to it’s class implementation, then it will be automatically registered. No need to remember about such silly things now!

No more statics in .net core all over the code 🙂

 All code posted here you can find on my GitHub:

3 thoughts on “Perfect console application in .net Core: set up dependency injection

  1. Saeid

    A lot of ppl that are still using their old IoC containers instead of the built-in one in .NET Core because of the methods like `RegisterAllTypesWithConvention`. project has these kinds of auto-wiring and it’s just an extension and not a new IoC container.

  2. Luciano Evaristo Guerche

    I’d rather use the same dependency injection engine used by core if possible.

    1. Michał Białecki Post author

      It is possible however, I don’t think it’s the best idea. You can use ‘built it’ DI, which comes with Microsoft.Extensions.DependencyInjection package. Nevertheless, SimpleInjector offers much more and is quite fast.


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