InvalidOperationException: Unable to resolve service for type 'System.Configuration.Configuration'

Question

Why am I getting this error?

InvalidOperationException: Unable to resolve service for type 'System.Configuration.Configuration' while attempting to activate 'HANACONNECT.Controllers.ServisController'.

My code in Program.cs

builder.Services.AddControllersWithViews();
builder.Services.AddDbContext<HANADbContext>();
var app = builder.Build();
var configuration = app.Configuration;

and code in ServisController.cs

namespace HANACONNECT.Controllers
{
    public class ServisController : Controller
    {
        
        private readonly Configuration _configuration;

        private readonly HANADbContext _context;
       
        public ServisController(Configuration configuration)
        {
            this._configuration = configuration;
        }
    }
}

Answer 1

When using DI you're generally always going to be injecting an Interface into your constructor. The DI container will then handle assigning the correct implementation according to your setup in Program.cs

Your code should look like this:

namespace HANACONNECT.Controllers
{
    public class ServisController : Controller
    {
        
        private readonly IConfiguration _configuration;

        private readonly HANADbContext _context;
       
        public ServisController(IConfiguration configuration)
        {
            _configuration = configuration;
        }
    }
}