public class AppConfig

{

    private static readonly IConfiguration _configuration;

    static AppConfig()

    {

        _configuration = new ConfigurationBuilder()

            .AddJsonFile("appsettings.json")

            .Build();

    }       

    public static string ConnectionString =>

        _configuration.GetConnectionString("DbConnection");

    public static SomeOption SomeOption =>

    {

        var someOptions = new SomeOption();

        _configuration.GetSection("SomeSection").Bind(someOption);

        return someOption;

    }

}