Can Factory pattern help with Dependency Injection? Provide example.

Short answer: Yes! Factory pattern can complement Dependency Injection (DI) by abstracting complex object creation logic, especially when the creation involves runtime parameters or complex setup that DI containers can’t handle easily. Example: Imagine a service that needs different data repositories based on a runtime parameter. public interface… IRepository { void……… Save(); } public class SqlRepository : IRepository { public…

Explain a bit more

void Save() => Console.WriteLine("Saving to SQL DB"); } public class InMemoryRepository : IRepository { public void Save() => Console.WriteLine("Saving in Memory"); } public interface IRepositoryFactory { IRepository CreateRepository(string repoType); } public class RepositoryFactory : IRepositoryFactory { public IRepository CreateRepository(string repoType) { return repoType.ToLower() switch { "sql" => new SqlRepository(), "memory" => new InMemoryRepository(), _ => throw new ArgumentException("Invalid repository type") }; } } // Consumer class with DI public class Service { private readonly… Yes! public class SqlRepository : IRepository { public void Save() => Console.WriteLine("Saving to SQL DB"); } public class InMemoryRepository : IRepository { public void Save()

Example code

=> Console.WriteLine("Saving in Memory"); }
public interface IRepositoryFactory
{ IRepository CreateRepository(string repoType); }
public class RepositoryFactory : IRepositoryFactory
{
public IRepository CreateRepository(string repoType)
{
return repoType.ToLower() switch
{ "sql" => new SqlRepository(), "memory" => new InMemoryRepository(), _ => throw new ArgumentException("Invalid repository type") }; }
} // Consumer class with DI public class Service
{
private readonly IRepositoryFactory _repositoryFactory;
public Service(IRepositoryFactory repositoryFactory)
{
_repositoryFactory = repositoryFactory;
}
public void SaveData(string repoType)
{
var repo = _repositoryFactory.CreateRepository(repoType); repo.Save(); }
} Here, DI injects the IRepositoryFactory while the factory manages object creation based on runtime input. This promotes loose coupling and flexibility. Strategy Design Pattern

Real-world example (ShopNest)

ShopNest payment fees use Strategy: IFeeCalculator with UPI/Card implementations chosen at runtime.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.