Dependency container: how to instantiate objects

I use Unity as a dependency injection mechanism. It contains interfaces / classes for the repository and manager classes. These storages are responsible for receiving / saving / updating data from / to the database and for managers to know about object relationships with other components / classes.

Implemented by factory to get an instance of the dependency container (1 instance per request). When a repository / manager class is created, it receives a dependency container as a constructor parameter and can create all other managers / repositories if necessary.

There are two ways to create business objects:

• When data is retrieved from the database repository, instances of objects are created and initialized with the corresponding database data, including the "Container" field.
• When an object is created in code to be placed in a DB, among others, it accepts the "IUnityContainer" parameter.

As a result, in any case, any business object has a dependency container inside, and if it needs to receive any data, it can get an instance of the corresponding manager and request the required data.

Problem statement: Last week I read a few questions / answers about SO that say the following:

• object instances should not have access to the dependency container;
• instead, they should get all the necessary interfaces in the constructor.

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, :

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3. , ( Linq2Sql EF), DependencyContainer, ( , SQL-, , , SQL). ?

:

Manager:

public abstract class ManagerBase : IManager
{
    protected ManagerBase(IUnityContainer container)
    {
        DependancyContainer = container;
    }

    protected readonly IUnityContainer DependancyContainer;

    ...
}

:

public abstract class RepositoryBase<T, TDb> : IRepository<T>
    where T : IEntity
    where TDb : class, IDbEntity, new()
{
    protected abstract ITable<TDb> GetTable();

    public IQueryable<T> GetAll()
    {
        return GetTable().Select(GetConverter());
    }

, : , "":

public class CountryRepository
    : RepositoryBase<ICountry, DbData.Country>, ICountryRepository
{   
    protected override Expression<Func<DbData.Country, ICountry>> GetConverter()
    {
        return dbEntity => new Country
        {
            DependancyContainer = DependancyContainer,

            Code = dbEntity.CountryCode,
            Name = dbEntity.CountryName,
        };
    }

, :

public class CountryManager : ManagerBase
{
    ICountry GetCountryById(int countryId)
    {
        ICountryRepository repository = DependancyContainer.Resolve<ICountryRepository>();
        return repository.GetAll()
            .Where(country=>country.Id==countryId)
            .SingleOrDefault()
            ;
    }
}