how to unit test asp.net core application with constructor dependency injection

Question

I have a asp.net core application that uses dependency injection defined in the startup.cs class of the application:

    public void ConfigureServices(ISer         


        

Answer 1

A simple way, I wrote a generic dependency resolver helper class and then built the IWebHost in my unit test class.

Generic Dependency Resolver

    public class DependencyResolverHelpercs
    {
        private readonly IWebHost _webHost;

        /// 
        public DependencyResolverHelpercs(IWebHost WebHost) => _webHost = WebHost;

        public T GetService()
        {
            using (var serviceScope = _webHost.Services.CreateScope())
            {
                var services = serviceScope.ServiceProvider;
                try
                {
                    var scopedService = services.GetRequiredService();
                    return scopedService;
                }
                catch (Exception e)
                {
                    Console.WriteLine(e);
                    throw;
                }
            };
        }
    }
}

Unit Test Project

  [TestFixture]
    public class DependencyResolverTests
    {
        private DependencyResolverHelpercs _serviceProvider;

        public DependencyResolverTests()
        {

            var webHost = WebHost.CreateDefaultBuilder()
                .UseStartup()
                .Build();
            _serviceProvider = new DependencyResolverHelpercs(webHost);
        }

        [Test]
        public void Service_Should_Get_Resolved()
        {

            //Act
            var YourService = _serviceProvider.GetService();

            //Assert
            Assert.IsNotNull(YourService);
        }


    }