ASP.NET Core: Dependency Injection for DB CF Migrations

Wow, you did very big mistake. You need not to add some your configuration to MyContext, because it's autogenerated file. What have you to do ? You have to add some your configuration file for example RegisterServices or it will be extension. For example

public static class ServiceCollectionExtensions
{
 public static IServiceCollection RegisterServices(
    this IServiceCollection services)
{
    services.AddTransient<ICountryService, CountryService>();
    // and a lot more Services

    return services;
}

}

And after that you have to Register this your configuration file in ConfigureServices, for example

public void ConfigureServices(IServiceCollection services)
{
// Add framework services.
services.AddMvc();

services.RegisterServices();
}

Finally, you can use Services or Repositories

public class HomeController : Controller 
{ 
private readonly ICountryService _countryService; 

 public HomeController(ICountryService countryService) 
 { 
    _countryService = countryService; 
 } 
// … 
}

Or, at the moment new in ASP.NET Core MVC is, that we can also inject this service into a MVC view. The following line defines the injection in a Razor view:

@inject DiViews.Services.ICountryService CountryService;

The first part after the @inject directive defines the interface. The second part is the name of the variable which holds our instance.

To inject a service globally into all Views, add this line to the _ViewImports.cshtml. In a complete new ASP.NET Core project, there is already a global injection defined for ApplicationInsights:

@inject Microsoft.ApplicationInsights.Extensibility.TelemetryConfiguration TelemetryConfiguration

We are now able to use the instance in our view:

@if (countryService.All().Any()) 
{ 
 <ul> 
    @foreach (var country in CountryService.All().OrderBy(x => x.Name)) 
    { 
        <p>@country.Name (@country.Code)</p> 
    } 
 </ul> 
 }

We can also use this service to fill select fields with the list of countries:

@Html.DropDownList("Coutries", CountryService.All() 
.OrderBy(x => x.Name) 
.Select(x => new SelectListItem 
{ 
    Text = x.Name, 
    Value = x.Code 
}))

I hope, it was helpful for you